Central Powers encircle Ivangorod

On 21 July 1915 the troops of General Remus von Woyrsch’s army group, attacking since 20 July, broke through the last Russian field position west of Ivangorod, the fortress of Dęblin. The Russian field units began to withdraw across the Vistula, leaving the fortress garrison in the forefield. The British chronology of the war records under this date the encirclement of Ivangorod by German and Austro-Hungarian troops. According to the Austrian official history, the order to close off the fortress was issued a day later, on 22 July, and the task went to the Austro-Hungarians.

The fortress, built by the Russians in the 19th century at the confluence of the Wieprz and the Vistula, guarded the crossing and the important Lublin–Ivangorod–Radom railway. Its forts stood on both sides of the river, but those on the left bank were already obsolete. The Russians had strengthened the forefield with a belt of field fortifications with partly concrete strongpoints. The commandant was Major-General Aleksei von Schwarz, who had also defended the fortress in the autumn of 1914. According to an Austrian study, the garrison consisted of two regiments of the 47th Infantry Division, two brigades of militia (opolchenie) and fortress artillery.

After breaking through the front at Zwoleń, Woyrsch ordered a pursuit so as not to let the Russians dig in again in front of the fortress. On 22 July he instructed General of Infantry Hermann Kövess to close off Ivangorod from the west, north of the railway from Radom, and to watch the Vistula downstream as far as the mouth of the Pilica. By the evening the Austro-Hungarian 16th Infantry Division and 9th Cavalry Division were already on the Vistula, within range of the fortress guns. The encirclement was, however, only partial. The eastern bank with the citadel remained in Russian hands, and the bridges still linked the fortress with the rest of the front.

It took a good deal of time to settle what to do next with Woyrsch’s troops. On the morning of 21 July the Chief of the German General Staff, Erich von Falkenhayn, proposed joining them with the German 9th Army and striking across the Vistula between Warsaw and Ivangorod, towards Siedlce and Łuków, into the rear of the Russians fighting at Lublin and Chełm. The Austrian Chief of Staff, Franz Conrad von Hötzendorf, preferred Woyrsch to cross the Vistula just above the fortress, at Novo-Alexandria, today’s Puławy, and support the Austro-Hungarian 4th Army. The dispute lasted several days. On 24 July the two chiefs of staff agreed on a compromise: Woyrsch’s Germans were to force the Vistula below Ivangorod, at the mouth of the Radomka, while Kövess’s group was to watch the river, close off the fortress from the west and attack it when the heavy artillery came up.

Kövess did not attack until 1 August. A few days later, as part of the general retreat from the Kingdom of Poland, the Russians blew up the fortifications and abandoned the fortress.