Military operations
Category
(1432)1915
January
- 02
- End of the Battle of SarikamishIn early January 1915 the Russians encircled the remnants of the Ottoman IX Corps at Sarikamish and took its commander. X Corps escaped over the mountains.
- Russians abandon UrmiaOn 2 January 1915 Russian troops withdrew from Urmia in northern Persia. Thousands of Assyrians and Armenians fled with them; Kurds and Turks took the town.
- 05
- German attack on EdéaOn 5 January 1915 the Germans attacked Edéa and Kopongo in Kamerun to push the Allies back from Yaoundé. Colonel Mayer's French garrison repulsed both attacks.
- Russians leave TabrizOn 5 January 1915 the last Russian troops left Tabriz, capital of Persian Azerbaijan, held since 1909. Most of the Armenians fled with them.
- 08
- Key eventStart of the battle of SoissonsOn 8 January 1915 the French attacked German trenches on the heights above the Aisne north of Soissons. Moroccan tirailleurs took Hill 132 in minutes.
- Turks take TabrizOn 8 January 1915 Kurdish and Turkish units entered Tabriz, abandoned by the Russians. The occupation of the capital of Persian Azerbaijan lasted three weeks.
- Battle of Kara Urgan beginsIn early January 1915 the Ottoman XI Corps attacked the Russians at Kara Urgan, on the road from Erzurum to Sarikamish. Then Enver Pasha left the front.
- 14
- End of the Battle of SoissonsOn 14 January 1915 the French, driven off the heights at Crouy by a German counter-attack, fell back across the flooded Aisne, losing over 5,000 prisoners.
- Capture of SwakopmundIn mid-January 1915 Union of South Africa forces took Swakopmund, the main port of German South West Africa, without a fight.
- 19
- Key eventFirst airship raid on EnglandOn 19 January 1915 the airships L 3 and L 4 bombed Great Yarmouth, King's Lynn and Norfolk villages. Four people died. It was the first airship raid on England.
- Germans capture JasinOn the morning of 19 January 1915 the Jasin garrison, out of ammunition and water, surrendered to Lettow-Vorbeck. 276 Indian and African soldiers were captured.
- 23
- Carpathian offensive beginsOn 23 January 1915 Austria-Hungary and the German South Army struck in the Carpathians to push the Russians back from the passes and relieve besieged Przemyśl.
- Defence of UpingtonOn 24 January 1915 the rebels of Maritz and Kemp, backed by German artillery, attacked Upington. Government troops beat them off after hours of fighting.
- 24
- Battle of Dogger BankOn 24 January 1915 Beatty's battlecruisers intercepted Hipper's squadron in the North Sea. The German cruiser Blücher was sunk; the other Germans escaped.
- Airship PL 19 shot down off LibauAt the end of January 1915 the German airship PL 19, damaged after a raid on Libau, came down in the Baltic. Seven airmen were taken prisoner by the Russians.
- 31
- German gas attack at BolimówOn 31 January 1915 the Germans attacked the Russians at Bolimów, firing 18,000 shells filled with tear gas. In the frost the gas had almost no effect.
- Idrisi takes the Farasan IslandsOn 31 January 1915 the Arab forces of Muhammad al-Idrisi, ruler of Asir, occupied the Farasan Islands in the Red Sea, abandoned by the Turks.
February
- 02
- Turkish advance guards on the Suez CanalOn 2 February 1915 the leading Turkish units approached Ismailia. In a sandstorm they clashed with Indian troops and dug in a few kilometres from the canal.
- Turks enter the Aden ProtectorateOn 2 February 1915 Ottoman troops from Yemen attacked the sultanate of Al-Bayda on the edge of the Aden Protectorate. Local tribes repulsed the attack.
- 04
- Winter Battle of Masuria beginsThe British chronology dates the start of the Winter Battle of Masuria to 4 February 1915. The Germans were still massing; the attack began on 7 February.
- Turks withdraw from the Suez CanalOn the morning of 4 February 1915 the Suez Canal's defenders found the main Turkish force had left in the night. Nearly 300 Turks surrendered at Serapeum.
- 17
- Austro-Hungarians retake Czernowitz againOn 17 February 1915 Karl Pflanzer-Baltin's Austro-Hungarian troops entered Czernowitz. The second Russian occupation of the Bukovinian capital was over.
- Loss of airships L 3 and L 4On 17 February 1915 engine failure and a snowstorm forced airships L 3 and L 4 down in Denmark. L 3 burned on Fanø; L 4 vanished at sea with four men.
- 19
- Fleet attack on the Dardanelles beginsOn 19 February 1915 British and French ships began shelling the forts at the entrance to the Dardanelles. At dusk some Turkish guns were still firing back.
- Austrians take StanisławówThe British chronicle records the Austrian capture of Stanisławów on 19 February 1915. Other sources say they entered a day later and held it for two weeks.
- Torpedoing of the tanker BelridgeOn 19 February 1915 a German submarine torpedoed the Norwegian tanker Belridge in the Strait of Dover. The damaged ship managed to reach port.
- 22
- End of the Second Battle of the Masurian LakesOn 22 February 1915 the Germans declared the winter battle in Masuria over. The Russian 10th Army left East Prussia, but most of its corps escaped.
- Start of the battle of PrzasnyszOn 22 February 1915 German divisions began to encircle Przasnysz in northern Mazovia, and the Russians sent fresh Siberian corps against their flank.
- Northern Force advances on WindhoekIn late February 1915 Botha's troops moved out of Swakopmund up the Swakop valley. The march across the Namib on the colonial capital, Windhoek, began.
March
- 01
- Blockade of German East AfricaOn 1 March 1915 Britain declared a blockade of the whole coast of German East Africa, to cut the colony off from supplies and hem in the Königsberg.
- Austrians bombard AntivariOn the night of 1–2 March 1915 Austro-Hungarian warships raided Antivari. They wrecked the pier and food stores and sank the King of Montenegro's yacht.
- 04
- Russians retake StanisławówOn 4 March 1915 the Russian 9th Army retook Stanisławów, captured by the Austrians two weeks earlier. The town stayed in Russian hands until June.
- Sinking of U-8On 4 March 1915 British destroyers destroyed the German submarine U-8 in the Strait of Dover after it had been detected thanks to indicator nets.
- 13
- End of the battle of Neuve ChapelleOn 13 March 1915 Haig halted the attack at Neuve Chapelle. The British held the village but did not reach Aubers Ridge. Shells had also run short.
- Sinking of the Swedish steamer HannaOn 13 March 1915 the Swedish steamer Hanna sank off Yorkshire. The British held she was torpedoed, but she may have struck a German mine.
- 15
- British squadron leaves SmyrnaOn 15 March 1915 the Admiralty recalled Admiral Peirse's squadron from Smyrna. The battleships went to the Dardanelles; smaller ships now blockaded the port.
- First aircraft attack on a merchant shipOn 15 March 1915 a German seaplane dropped bombs on the British steamer Blonde off the Kent coast. None hit, and the ship got away safely.
- 18
- Fleet attack in the Dardanelles repulsedOn 18 March 1915 the Allies attacked the forts at the Dardanelles Narrows. Bouvet, Irresistible and Ocean sank on Turkish mines and the fleet withdrew.
- Russians take MemelOn 18 March 1915 Russian militia units entered Memel from Courland. They took hostages and plundered the town and the surrounding villages.
- 21
- Germans retake MemelOn 21 March 1915 the Germans drove the Russians out of Memel after street fighting. In the pursuit, aided by warships, they took about 500 prisoners at Palanga.
- First airship raid on ParisOn the night of 20–21 March 1915 two German airships bombed Paris and its suburbs. Z X, damaged by fire from the ground, crashed on the way back.
April
- 12
- Battle of Shaiba beginsOn 12 April 1915 Turkish troops and the Arab allies of Süleyman Askerî attacked the British camp at Shaiba near Basra. The attacks were repulsed.
- First advance on JaundeIn April 1915 Col. Mayer's columns set out from Edea towards Jaunde, the capital of German Kamerun. On 14 April they fought their way across the Kele river.
- 14
- Germany accuses the French of using gasOn 14 April 1915 a German communiqué accused the French of using bombs with "asphyxiating" gas near Verdun. There were more such accusations in those days.
- End of the battle of ShaibaOn 14 April 1915 British and Indian troops took the Turkish trenches by Barjisiyah wood. The Turks fled Basra and their commander Süleyman Askerî shot himself.
- 17
- Key eventBritish capture Hill 60On 17 April 1915 the British blew mines under Hill 60 south of Ypres and took it within minutes. Over the following days they beat off counter-attacks.
- Allies advance on GaruaIn April 1915 Col. Cunliffe brought reinforcements and a naval gun to Garua. The Allies began to tighten the ring around the German fortress in Kamerun.
- Skirmish at Hafiz KorIn mid-April 1915 Mohmand tribesmen invaded British Indian territory near Shabkadar. Troops from Peshawar drove them back at Hafiz Kor.
- 22
- Key eventSecond Battle of Ypres beginsOn 22 April 1915 the Germans released a cloud of chlorine at Ypres. Two French divisions broke, and a gap several kilometres wide opened north of the town.
- Key eventBattle of Gravenstafel Ridge beginsOn the night of 22–23 April 1915 Canadians counter-attacked at Ypres to close the gas-attack gap. Of 1,500 men who charged the wood, under 500 were left.
- 25
- Key eventAllies land at GallipoliOn 25 April 1915 British, Australian, New Zealand and French troops landed at the Dardanelles. The Turks put up fierce resistance.
- Russians bombard the Bosporus againOn 25 April 1915, the day of the Gallipoli landings, the Russian Black Sea Fleet shelled the Bosporus forts to tie down Turkish forces near Constantinople.
- Clash at GibeonIn late April 1915 General McKenzie's mounted troops caught the retreating Germans at Gibeon. A night ambush failed, but in the morning the Germans were routed.
- 26
- Internment of the Kronprinz WilhelmOn 26 April 1915 the German auxiliary cruiser Kronprinz Wilhelm, the last Kaiserliche Marine raider then at large on the oceans, was interned at Newport News.
- Sinking of the cruiser Léon GambettaDuring the night of 26–27 April 1915 the Austro-Hungarian submarine U-5 sank the French cruiser Léon Gambetta at the mouth of the Adriatic. 684 men died.
May
- 01
- Key eventStart of the Battle of GorliceOn 1 May 1915 German and Austro-Hungarian guns began shelling the Russians at Gorlice, and on 2 May Mackensen's army attacked and broke through the front.
- Battle of DilmanOn 1 May 1915 at Dilman in Persian Azerbaijan, Russians and Armenian volunteers under Nazarbekian repulsed Halil Bey's corps. The Turks withdrew at night.
- Torpedoing of the tanker GulflightOn 1 May 1915 U-30 torpedoed the American tanker Gulflight off the Scilly Isles. She did not sink, but two seamen drowned and the master died of heart failure.
- 07
- Germans occupy LibauOn 7 May 1915, supported by the fleet, the Germans entered Libau, a naval port in Courland. The Russian garrison withdrew, blowing up forts and depots.
- Key eventSinking of the LusitaniaOn 7 May 1915 U-20 torpedoed the British liner Lusitania off Ireland. Within 18 minutes almost 1,200 people died, including more than a hundred Americans.
- 08
- Key eventBattle of Frezenberg Ridge beginsOn 8 May 1915, after a hurricane bombardment, the Germans broke the British front on Frezenberg Ridge near Ypres. The last reserves closed the gap at night.
- End of the Second Battle of KrithiaOn 8 May 1915 New Zealanders, Australians and French renewed the attack on Krithia. Thousands of killed and wounded bought gains measured in hundreds of metres.
- Battle of Sanok and Rzeszów beginsOn 8 May 1915 the Russians, driven from the Wisłoka, tried to halt the Central Powers' pursuit on the Wisłok. They were to die in their positions, not retreat.
- 09
- Key eventBritish attack Aubers RidgeOn 9 May 1915 the British First Army attacked Aubers Ridge to support the French in Artois. Machine-gun fire stopped the attack in no man's land.
- Key eventSecond Battle of Artois beginsOn 9 May 1915 the French Tenth Army attacked near Arras. Pétain's corps reached Vimy Ridge in two hours, but without reserves it could not hold it.
- 13
- Battle of Frezenberg Ridge endsOn 13 May 1915 the Germans made their last attack at Ypres in the Battle of Frezenberg Ridge. Dismounted cavalry and British infantry held the front.
- South Africans occupy WindhoekOn 12 May 1915 Botha rode into Windhoek, surrendered without a fight by the town authorities. The capital of German South West Africa passed to the Union.
- Sinking of the battleship GoliathOn the night of 12/13 May 1915 the Turkish destroyer Muavenet-i Milliye crept into the Dardanelles and torpedoed the British battleship Goliath. About 570 died.
- 14
- Central Powers take JarosławIn mid-May 1915 the German Guard and the Austro-Hungarian VI Corps took the Russian bridgehead at Jarosław and reached the San. The town suffered from shelling.
- End of the battle of Sanok and RzeszówIn mid-May 1915 the Russians withdrew from western Galicia behind the San. The Central Powers took Sanok and Rzeszów and 130,000–140,000 prisoners.
- 19
- Russians enter VanOn 19 May 1915 Russian troops entered Van, preceded a day earlier by Armenian volunteers. The city, defended by the Armenians, was free.
- The Puławy Legion at PakosławOn the night of 19–20 May 1915 the Puławy Legion attacked the Germans at Pakosław near Iłża. Of 493 men it lost 42 killed, 60 wounded and 11 missing.
- 24
- Key eventGerman gas attack at BellewaardeAt dawn on 24 May 1915 the Germans released chlorine at Ypres on a 7 km front, took Mouse Trap Farm and part of Bellewaarde Ridge but did not break through.
- Fighting to retake Przemyśl beginsOn 24 May 1915 Mackensen's army struck at Radymno to cut Przemyśl off from the east. The Russians lost Radymno and thousands of men as prisoners.
- Battle of the Stryj beginsOn 24 May 1915 the South Army began shelling Russian positions before Stryj. Linsingen massed his forces for one blow, but the infantry stuck in the wire.
- Italians cross the Austrian borderOn 24 May 1915 Italian troops crossed the border of Austria-Hungary along almost its whole length. The Austrians fell back behind the Soča, blowing up bridges.
- Russians retake UrmiaOn 24 May 1915 the Russians returned to Urmia, left a few days earlier by the Turks and Kurds. An occupation tragic for the Christians was over.
- 25
- End of the Second Battle of YpresOn 25 May 1915 the Second Battle of Ypres died down. After five weeks of fighting and gas attacks the Germans had shrunk the salient but not taken Ypres.
- End of the Battle of FestubertOn 25 May 1915 the London 47th Division took a German trench at Festubert and French decided to halt the offensive. Ten days of fighting cost 16,600 men.
- Sinking of the battleship TriumphOn 25 May 1915 Otto Hersing's German U-21 torpedoed the British battleship Triumph off Gaba Tepe. She sank before the eyes of the ANZAC troops.
- Italian fleet begins operations in the AdriaticOn 25 May 1915 Italian sailors took the Austrian post at Porto Buso. The day before, the Austro-Hungarian fleet had shelled Ancona and the Italian coast.
- 31
- Siege of Garua beginsOn 31 May 1915 British and French troops began bombarding the German fortress of Garua in Kamerun. Heavy guns quickly silenced its artillery.
- Key eventFirst airship raid on LondonIn the night of 31 May – 1 June 1915 the German airship LZ 38 bombed east London. Seven people were killed, including children, and 35 were injured.
- Second Battle of Qurna beginsOn 31 May 1915 Townshend's division attacked Turkish posts north of Qurna in Arab boats across flooded marshes and took them before noon.
June
- 03
- The Central Powers retake PrzemyślEarly on 3 June 1915 German and Austro-Hungarian troops entered Przemyśl, abandoned by the Russians. Russian rule in the town had lasted 73 days.
- British take AmaraOn 3 June 1915 a few British launches carrying Townshend sailed up the Tigris to Amara. Over a thousand Turkish soldiers surrendered to a handful of sailors.
- End of the battles of Stryi and DrohobyczBy 3 June 1915 the Russians had fallen back from Stryi and Drohobycz to the Dniester. The oil basin was free, but they still held a bridgehead on the river.
- 07
- Warneford destroys airship LZ 37On 7 June 1915 British airman Reginald Warneford bombed the airship LZ 37 in mid-air over Ghent. The burning wreck fell on a convent in Sint-Amandsberg.
- Allies abandon the march on JaundeOn 7 June 1915 Gen. Dobell, still without news of Aymerich's columns, halted the march on Jaunde. Col. Mayer's troops were to fall back to the Ndupe river.
- 10
- Capitulation of GaruaOn 10 June 1915, after a failed breakout and a mutiny of his African troops, Capt. von Crailsheim gave up Garua unconditionally. The Allies took 37 Germans.
- Battle of Żydaczów beginsOn 10 June 1915 the South Army, thrown back over the Dniester the day before, struck upstream at Żydaczów, into the flank of the Russians advancing on Stryj.
- 11
- End of the Battle of PrzemyślA British chronology ends the Battle of Przemyśl on 11 June 1915. After the fortress fell, the front halted at Mościska and Mackensen prepared to hit Lviv.
- End of the Battle of the StryiOn 11 June 1915 the South Army, earlier pushed back over the Dniester, attacked again near Żydaczów. The British chronology ends the Stryi battle that day.
- 12
- Battle of Mościska and Lubaczów beginsOn 12 June 1915 Mackensen's troops crossed the San and the Lubaczówka near Sieniawa. The battle that was to open the road to Lviv had begun.
- Battle of Rarańcza beginsOn 12 June 1915 the Legions' Second Brigade took Rarańcza in Bukovina unopposed, but was held up by Russian trenches on the hills above Rokitna in Bessarabia.
- 15
- Battle of Mościska and Lubaczów endsOn 15 June 1915 Mackensen's armies broke the second Russian line at Nahaczów and Oleszyce. Brusilov ordered a retreat to the Gródek line in front of Lviv.
- Battle of Rarańcza endsOn 15 June 1915 XI Corps fell back to the Rokitna and the Second Brigade dug in at Rarańcza, where the uhlans killed in the charge at Rokitna were buried.
- 22
- Austro-Hungarians retake LvivOn 22 June 1915 troops of the Austro-Hungarian Second Army entered Lviv. After 293 days the Russian occupation of the capital of Galicia came to an end.
- End of the battle of ŻydaczówOn 22 June 1915 the battle of Żydaczów ended. Threatened from the north, the Russians gave up the south bank of the Dniester; the South Army prepared to cross.
- British capture BukobaOn 22–23 June 1915 a British force sailed across Lake Victoria to Bukoba, broke the German defence, destroyed the wireless station and re-embarked.
- 27
- British advance up the EuphratesOn 27 June 1915 Gen. Gorringe's flotilla and brigade crossed the Hammar Lake and set off up the Euphrates towards Nasiriyah. The first obstacle was a dam.
- Battle of the Gniła Lipa beginsOn 27 June 1915, after several days of fighting at Bóbrka and Bukaczowce, the Russians fell back to the Gniła Lipa. The Austrians took Halicz unopposed.
- 28
- Start of the fighting for Gully RavineOn 28 June 1915 British troops and Gurkhas at Helles took five lines of Turkish trenches by Gully Ravine. A Scottish brigade alongside lost half its men.
- End of the first advance on YaoundéOn 28 June 1915 German attacks on Col. Mayer's troops, withdrawn to the Kele line, ceased. The failed advance on Yaoundé cost the Allies over 300 casualties.
- Allies take NgaundereOn 28 June 1915 Lt-Col. Webb-Bowen's column fought its way in a storm onto the plateau near Ngaundere in Kamerun. Next day the Allies took the town unopposed.
- 29
- Start of the First Battle of the IsonzoThe British chronology dates the start of the First Battle of the Isonzo to 29 June 1915. Yet the Italians had been attacking on the Soča since 23 June.
- End of the Battle of the Gniła LipaOn 29 June 1915 the Central Powers crossed the Gniła Lipa but met strong resistance. The Russians fell back to the Złota Lipa only on the night of 1–2 July.
July
- 01
- Second Battle of Kraśnik beginsOn 1 July 1915 the Austro-Hungarian Fourth Army advanced between the Vistula and the Bystrzyca towards Lublin. At Kraśnik it met fortified Russian positions.
- South Africans take OtavifonteinOn 1 July 1915 Manie Botha's mounted brigade surprised the Germans near Otavi after a night march and took Otavifontein, the last good water before their line.
- 02
- End of the fighting for Gully RavineOn 2 July 1915 the Turks attacked across open ground to retake lost trenches above Gully Ravine at Helles. British batteries and a destroyer broke the attack.
- Naval battle off GotlandOn 2 July 1915 Russian cruisers forced the German minelayer Albatross to run aground on Gotland. Off Rozewie the E9 torpedoed the Prinz Adalbert.
- 04
- Turks capture LahejOn 4 July 1915 Ottoman troops from Yemen broke into Lahej near Aden. An exhausted British column fell back, and the Sultan was mortally wounded.
- Serbs in central AlbaniaThe British chronology records the Serbian capture of Durrës on 4 July 1915. In reality they held Tirana and Elbasan, but did not enter Esad's city.
- 07
- End of the First Battle of the IsonzoOn 7 July 1915 Cadorna halted the attacks on the Isonzo. After two weeks the Italians had won only a strip of the Karst at Sagrado, losing some 15,000 men.
- Sinking of the cruiser AmalfiOn 7 July 1915 the German submarine UB-14, sailing under the Austro-Hungarian flag as U-26, sank the Italian armoured cruiser Amalfi off Venice.
- 11
- Destruction of the cruiser KönigsbergOn 11 July 1915 the British monitors Severn and Mersey, directed from an aircraft, wrecked the cruiser Königsberg in the Rufiji delta. Her crew blew her up.
- Italians occupy PelagosaOn 11 July 1915 Italian sailors landed on the Austrian islet of Pelagosa in the middle of the Adriatic and set up an observation and signal post there.
- 13
- Central Powers' great offensive in the east beginsOn 13 July 1915 the Germans struck from East Prussia towards the Narew. An offensive began that was to drive the Russians out of the Kingdom of Poland.
- Battle of the Narew and Biebrza beginsOn 13 July 1915 Gallwitz's and Scholtz's armies attacked the Russian front between the Vistula and Biebrza, aiming at the Narew crossings and Warsaw's rear.
- Second Battle of Przasnysz beginsOn 13 July 1915, after a bombardment of several hours from some 800 guns, Army Group Gallwitz broke the Russian First Army's main defence line at Przasnysz.
- Battles of Masłomęcz and Grabowiec beginOn 13 July 1915 the German Army of the Bug took up positions between Hrubieszów and Grabowiec. The attack on the Russian Thirteenth Army began on 15 July.
- 17
- Battle of SiennoOn 17 July 1915 Woyrsch's Silesian Landwehr broke the Russian front at Sienno on the west bank of the Vistula. The Russians fell back towards Ivangorod.
- End of the second battle of PrzasnyszBy 17 July 1915 the Germans had pushed the Russian 1st Army back about 30 km from Przasnysz and Ciechanów to fortified bridgeheads on the Narew.
- 18
- Start of the Second Battle of the IsonzoOn 18 July 1915 the Italians struck on the Isonzo for the second time. With much stronger artillery they attacked Monte San Michele and Sei Busi on the Karst.
- Sinking of the cruiser Giuseppe GaribaldiOn 18 July 1915 the Austro-Hungarian submarine U-4 sank the Italian armoured cruiser Giuseppe Garibaldi off Cavtat as it shelled the railway in Dalmatia.
- End of the battles of Masłomęcz and GrabowiecOn 18 July 1915 the Russian Thirteenth Army still held off the Bug Army near Hrubieszów and Grabowiec. It fell back that night as the front broke at Krasnystaw.
- End of the Battle of KrasnystawOn 18 July 1915 the Germans held Krasnystaw and the Wieprz bridgehead despite Russian Guards counter-attacks. At night the Russians fell back near the railway.
- 19
- End of the second battle of KraśnikOn the night of 18–19 July 1915 the Russians abandoned their positions at Kraśnik and Urzędów and fell back closer to Lublin. As they left, they burned Urzędów.
- Battles of Hrubieszów and Wojsławice beginOn 19 July 1915 the Russians fell back to a new line running west from Hrubieszów. The Army of the Bug followed them and stopped before more trenches.
- 20
- Key eventStart of the Battle of Le LingeOn 20 July 1915 French chasseurs alpins attacked the German positions on the Linge ridge in the Vosges. The first assault collapsed under fire from bunkers.
- Start of the second battle of IvangorodOn 20 July 1915 Woyrsch's troops attacked the last Russian field position before the fortress of Ivangorod (Dęblin). The Austro-Hungarians entered Radom.
- 21
- Central Powers encircle IvangorodOn 21 July 1915 Woyrsch's troops reached Ivangorod. Kövess's Austro-Hungarians closed it off from the west; the Germans prepared to cross the Vistula.
- End of the second battle of IvangorodOn 21 July 1915 the Silesian Landwehr broke the front at Zwoleń. The Russians left Ivangorod's forefield for the Kozienice–Gniewoszów line on the Vistula.
- 30
- Battles of Hrubieszów and Wojsławice endOn 30 July 1915 the Russian 13th Army began to retreat from Hrubieszów. After twelve days of fighting the Bug Army reached Strzelce and Leszczany.
- End of the Battle of BiskupiceOn 30 July 1915, after their defeat at Biskupice, the Russians fell back all along the front between the Vistula and the Bug. The Austro-Hungarians took Lublin.
- Start of the Battle of KupiškisOn 30 July 1915 the Russian 5th Army struck at Kupiškis in Lithuania, into the gap between Niemen Army cavalry corps due to set off for Vilna and Dvinsk.
August
- 05
- Key eventGermans occupy WarsawOn 5 August 1915 troops of the German Ninth Army entered Warsaw, abandoned by the Russians overnight. Russian rule, in place since 1815, came to an end.
- Central Powers take IvangorodOn 5 August 1915 Vienna announced the capture of Ivangorod. A day earlier the Austro-Hungarians had entered forts the Russians left on the Vistula's left bank.
- Turks occupy VanIn early August 1915 Ottoman troops returned to Van, abandoned by the Russians, and at Bergri Kurds attacked columns of Armenian refugees.
- 06
- Landing at Suvla BayOn the evening of 6 August 1915 British IX Corps began landing at Suvla Bay on Gallipoli. The Turks had only three battalions there and were caught unawares.
- Battle of Sari Bair beginsOn 6 August 1915 Australians took the Turkish trenches at Lone Pine, and after dark columns from Anzac set off up the gullies towards the Sari Bair heights.
- 08
- British occupy BushehrOn 8 August 1915 the British occupied the Persian port of Bushehr and took over its administration, in reply to the July Tangestani attack on the Residency.
- Sinking of the battleship Barbaros HayreddinOn 8 August 1915 the British submarine E11 torpedoed the Turkish battleship Barbaros Hayreddin in the Sea of Marmara, off Bulair. About 250 men died.
- Start of the German attack on the Gulf of RigaOn 8 August 1915 German minesweepers began sweeping mines in the Irbe Strait. They lost two ships, and in the afternoon Admiral Schmidt broke off the attack.
- 10
- End of the Battle of Sari BairAt dawn on 10 August 1915 the Turks under Mustafa Kemal retook Chunuk Bair and drove the British off the Sari Bair ridge. The Anzac offensive was over.
- End of the Second Battle of the IsonzoThe Austro-Hungarian official history ends the Second Battle of the Isonzo on 10 August 1915. After Italy's 3 August order, the Karst fighting went on a week.
- Loss of airship L 12On the night of 9–10 August 1915 guns at Dover hit airship L 12. It came down in the sea, was towed to Ostend and was bombed there by RNAS airmen.
- 19
- E1 torpedoes the battlecruiser MoltkeOn 19 August 1915 the British submarine E1 torpedoed the German battlecruiser Moltke in the Baltic. The ship did not sink, but was out of service for a month.
- Attack on the submarine E13On 19 August 1915 German torpedo boats shelled the British submarine E13, aground in Danish waters in the Sound. Fifteen British sailors were killed.
- Sinking of the ArabicOn 19 August 1915 U-24 torpedoed the liner Arabic off Ireland without warning. 44 people died, Americans among them, setting off a new crisis with the USA.
- Baralong sinks U-27On 19 August 1915 the British Q-ship Baralong sank U-27. Her crew shot the submarine's survivors, which became a notorious affair.
- 21
- Attack on Scimitar HillOn 21 August 1915 the British attacked the hills above Suvla Bay. Twice they took the top of Scimitar Hill, but lost 5,300 men and returned to their positions.
- Lifeboats of the Ruel fired onOn 21 August 1915 a German U-boat sank the British steamer Ruel and fired on the lifeboats with the crew. One seaman was killed and the master wounded.
- End of the German attack on the Gulf of RigaOn 21 August 1915 German ships left the Irbe Strait. They had broken into the Gulf of Riga but neither destroyed the battleship Slava nor mined Moon Sound.
September
- 09
- Start of the Battle of DvinskOn 9 September 1915 the right wing of the German Niemen Army set off for Dvinsk, to reach the Dvina and cover the attack on Vilna from the north.
- Start of the Battle of VilnaOn 9 September 1915 the German 10th Army struck north of Vilna, into the gap between two Russian armies. General Garnier's cavalry pushed into the breach.
- Renewed attack on BushehrOn 9 September 1915 several hundred Tangistanis attacked the British lines at Bushehr. They were repulsed after hours of fighting that saw a cavalry charge.
- 16
- Germans take PinskIn mid-September 1915 the German Army of the Bug took Pinsk in Polesia. The Russians fell back behind the Yaselda and the Ogiński Canal into the Pripet marshes.
- Battle of Tarnopol endsOn 16 September 1915 Ivanov ended his counter-offensive and pulled back to the Seret. The Russians had halted the Austro-Hungarian offensive in East Galicia.
- 25
- Key eventBattle of Loos beginsOn 25 September 1915 the British attacked at Loos behind chlorine gas, taking the village, Hill 70 and the Hohenzollern Redoubt, but reserves were too far back.
- Key eventThird Battle of Artois beginsOn 25 September 1915 the French Tenth Army again attacked Vimy Ridge. The left wing reached Souchez, but on the rest of the front the attack broke down.
- Key eventSecond Battle of Champagne beginsOn 25 September 1915 two French armies attacked in Champagne. They took the German first line and 14,000 prisoners, but the second position stopped the attack.
October
- 08
- End of the Battle of LoosOn 8 October 1915 the Germans tried to retake Loos and their lost trenches. The Allies repulsed them, and British nomenclature ends the battle that day.
- Germans take the Gauala ridgeOn the night of 8/9 October 1915 the besieged Mora mountain garrison took the Gauala ridge, from which the Allies had shelled German positions for a year.
- 09
- Capture of BelgradeOn 9 October 1915 the Serbs left their capital. The Habsburg flag flew over Kalemegdan, the Germans took the royal palace. Belgrade fell after three days.
- Third skirmish at Hafiz KorIn early October 1915 troops from Peshawar again routed the Mohmands at Hafiz Kor. Armoured cars were used in combat in India for the first time.
- 11
- Fighting between Bulgaria and Serbia beginsOn 11 October 1915 the first shots were fired on the Bulgarian-Serbian frontier. Bulgaria had not yet declared war, but its armies were ready to attack.
- Capture of SmederevoOn 11 October 1915 the German 25th Reserve Division took Smederevo on the Danube. The British chronology credits the Austrians, but the Germans took the town.
- 13
- Airship raid on TheatrelandOn the evening of 13 October 1915 the airship L 15 bombed London's Theatreland. The raid by five airships killed 71 people and injured 128.
- First clashes between the French and the BulgariansIn mid-October 1915 the French moved from Salonika up the Vardar into Serbia. They first fought the Bulgarians on 21 October near Strumica station.
- 15
- Third Battle of Artois endsOn 15 October 1915 General d'Urbal ordered the 10th Army to fortify its gains for the winter. The French took Souchez, but Vimy Ridge stayed in German hands.
- Bulgarians take VranjeIn mid-October 1915 the Bulgarian Second Army reached Vranje on the South Morava and cut the Niš–Salonika railway, Serbia's main route to the Allies.
- 21
- Bombardment of DedeagachOn 21 October 1915 British, French and Russian ships shelled the Bulgarian port of Dedeagach and the coast to Porto Lagos, wrecking barracks and rolling stock.
- Bulgarians take VelesAround 20 October 1915 Bulgarian cavalry took Veles on the Vardar. The Salonika–Skopje railway was cut and the Serbs were cut off from the French.
- 22
- Bulgarians take Kumanovo and SkopjeOn 22 October 1915 the Bulgarian 3rd Division entered Skopje, two days after taking Kumanovo. Serbia lost the most important road junction in its south.
- Austro-Hungarians take ŠabacThe British chronology records the capture of Šabac under 22 October 1915. Austro-Hungarian Landsturm had entered the town unopposed on 20 October.
- Legions capture KukleOn 22 October 1915 Rydz-Śmigły's legionaries took the village of Kukle in Volhynia, helping to close the gap a Russian attack had torn in the Styr front.
- 24
- Bulgarians take NegotinOn 24 October 1915 the Bulgarians took Negotin on the lower Timok. Two days later they met the Austrians on the Danube, opening the river route to Turkey.
- Fighting begins at KrivolakIn late October 1915 the French 57th Division reached Krivolak on the Vardar, 30 km from Veles. It met the Bulgarians there but never reached the Serbs.
November
- 01
- Capture of KragujevacOn 1 November 1915 the Germans and Austrians entered Kragujevac. The Serbs left without a fight, having blown up the country's only arsenal the day before.
- End of the Battle of DvinskOn 1 November 1915 the German attack on Dvinsk petered out. The Russians kept the town and Dvina bridgeheads; the front froze there for over two years.
- 05
- Bulgarians take NišOn 5 November 1915 the Bulgarian First Army entered Niš, Serbia's wartime capital. The Central Powers won the railway to Sofia and Constantinople.
- Battle of Kačanik beginsIn early November 1915 the Bulgarians advanced through the Kačanik gorge towards the Field of Kosovo to cut the Serbs' last road south. The Serbs resisted.
- 06
- End of the Second Battle of ChampagneOn 6 November 1915 the last fighting of the Second Battle of Champagne died down. German counter-attacks retook the Butte de Tahure and Hill 199 near Massiges.
- Submarine attack on SollumOn 6 November 1915 the German submarine U-35 sank the Egyptian coastguard cutter Abbas in the bay of Sollum and damaged the Nur al-Bahr.
- Capture of Mount BanyoAt dawn on 6 November 1915 Cunliffe's Nigerians reached the top of Mount Banyo in Kamerun. The German garrison fled at night in a storm, but most were caught.
- 07
- Sinking of the cruiser UndineOn 7 November 1915 the British submarine E19 torpedoed the light cruiser Undine, escorting a ferry to Sweden, north of Rügen. About 24 men were killed.
- Sinking of the AnconaOn 7 November 1915 a submarine flying the Austro-Hungarian flag shelled and sank the Italian liner Ancona off Sardinia. About 200 died, Americans among them.
- 10
- Start of the Fourth Battle of the IsonzoOn 10 November 1915, after a short, concentrated bombardment, the Italians again attacked Gorizia and Monte San Michele. By evening almost all were repulsed.
- Legions capture Polish HillOn 10 November 1915 the Second Brigade and Austro-Hungarian troops took the Russian positions at Kostiuchnówka. The Germans named the hill Polish Hill.
December
- 02
- Bulgarians take BitolaIn early December 1915 Bulgarian cavalry entered Bitola, the second city of Serbian Macedonia. Its defenders fell back not to Salonika but to Albania.
- French abandon KrivolakIn early December 1915 the French withdrew from Krivolak and the loop of the Vardar and Crna Reka before the Bulgarians could strike at them.
- 06
- Austro-Hungarian squadron shells DurrësOn 6 December 1915 the cruiser Helgoland and destroyers sank sailing vessels carrying supplies for the Serbs, some at Durrës. A day earlier Novara raided Medua.
- Capture of PećIn early December 1915 the Austro-Hungarians took Montenegrin Peć, through which the main Serbian forces had retreated, and found nearly 100 hidden guns there.
- 07
- Key eventSiege of Kut beginsOn 7 December 1915 Ottoman troops began to surround Kut, where Townshend's division stood at bay. Nureddin called on the British to surrender.
- Fighting at KosturinoOn 7 December 1915, in thick fog, the Bulgarians broke the front of the British 10th Division at Kosturino. The British retreat from Serbian Macedonia began.
- 15
- Last Entente troops leave MacedoniaIn mid-December 1915 the last Entente troops left Serbian Macedonia. The Bulgarians halted at the Greek border and the Allies fell back towards Salonika.
- Ottoman troops occupy Qasr-e ShirinOn 15 December 1915 Ottoman troops took Qasr-e Shirin on the Persian border. The Turks were coming to help the Germans and Persian émigrés against the Russians.
- 17
- Sinking of the cruiser BremenOn 17 December 1915 the German light cruiser Bremen struck Russian mines off Windau and sank with the torpedo boat V 191. Some 200–250 sailors died.
- Loss of the airship LZ 39On 17 December 1915 Russian artillery hit the German airship LZ 39 over Rovno. The crew managed to land near Lutsk, but the ship could not be saved.
- 25
- Christmas Eve assault on KutOn 24 December 1915 the Turks made their biggest assault on the Kut fort. Fighting lasted into the night; on Christmas Day the defenders held the ruined fort.
- Clash at Wadi MajidOn Christmas Day 1915 the Western Frontier Force attacked the Senussi camp near Mersa Matruh and drove the order's forces out of Wadi Majid.
- 29
- Austro-Hungarian raid on DurrësOn 29 December 1915 the cruiser Helgoland and five destroyers raided Durrës. Two destroyers sank on mines and the rest barely escaped pursuit.
- Möwe sails on her first cruiseOn 29 December 1915 the auxiliary cruiser Möwe, disguised as a freighter, put to sea from Wilhelmshaven to lay mines and sink Allied ships.