Battle of Biskupice begins

On 29 July 1915, after a pause of several days, the troops of Field Marshal August von Mackensen again attacked along the whole front between the Vistula and the Bug. The most important blow was struck by the German 11th Army west of the Wieprz, in the direction of Biskupice, a former small town on the Giełczewka (PL), south-east of Lublin. That same day the Germans broke through the Russian lines and reached the railway from Lublin to Chełm. The German list of battles, and following it the British chronology of the war, calls this fighting the Battle of Biskupice. It lasted two days.

Mackensen’s new plan

After the victory at Krasnystaw in mid-July the advance of the Central Powers slowed down again. The Russians fell back to a prepared line south of the Lublin – Chełm railway, then defended it stubbornly and counter-attacked. On 20–22 July the Austro-Hungarian 4th Army broke through the Russian positions on the Chodel over a width of 23 kilometres and took more than 12,000 prisoners, but got no further. The Bug Army advanced step by step at Hrubieszów and Wojsławice. Mackensen concluded that pushing the Russians back frontally would decide nothing. On 24 July he announced that the new blow would come from the centre of the front, from a narrow sector west of the Wieprz. From 24 to 28 July the 4th and 11th Armies halted their advance and regrouped.

The main blow was to be led by General Otto von Emmich. According to the Austrian official history he was given seven infantry divisions: the divisions of the XXII and X Reserve Corps and of X Corps, as well as the 119th Infantry Division. To these was added the Guard Cavalry Division. The Prussian Guard and the Austro-Hungarian VI Corps on the east bank of the Wieprz were to move only once Emmich’s wedge had begun to take effect. The objective was the Lublin – Chełm railway, part of the Vistula Railway. Along it the Russians were moving troops and supplies out of Congress Poland.

Facing them stood the Russian 3rd Army of General Leonid Lesh. In mid-July the Russian command had reinforced it with two corps from the reserve: the Guard and II Siberian Corps. It was II Siberian Corps that was defending at Biskupice.

The breakthrough

On 29 July the attack went according to plan. According to the Austrian official history, Emmich’s wedge drove II Siberian Corps from its positions, and the Siberians suffered heavy losses in the process. The Germans’ right wing reached the railway line at Trawniki. The left wing halted on the hills south of Biskupice. The German communiqué of 30 July reported the capture of the line Piaski – Biskupice and of the railway east of it, as well as many thousands of prisoners and three guns. On the east bank of the Wieprz the Prussian Guard moved off in the late afternoon, but did not break the Russian Guard. Some of Emmich’s units, however, won a bridgehead on the east bank of the river. From there an attack was planned for 30 July which was to catch in a pincer the Russians facing the Prussian Guard and VI Corps.

The neighbouring armies did not advance so quickly. The Austro-Hungarian XVII Corps of the 4th Army spent the whole day storming the hills north-east of the village of Chmiel, protected, according to the Austrian official history, by seven belts of wire. Only the third assault, just before dawn, won it the main Russian position. The Austro-Hungarian communiqué even spoke of five assaults. The Bug Army also met fierce resistance and by evening had advanced only slightly. The same night, of 28–29 July, the troops of General Remus von Woyrsch crossed the Vistula at Ryczywół, north of Ivangorod.

The defeat at Biskupice and Chmiel settled the matter. The Russian command did not want to accept a decisive battle. During the night of 29–30 July it broke off the fight and ordered the three armies between the Vistula and the Bug to retreat northwards.