By November 1915, the invading forces had reached the River Khstors and sought to force a crossing at Gnizediu, where there were both bridges and a ford. Elements of the Russian Fourth Army defended the town, but were critically short on ammunition and artillery compared to the advancing Germans and Austro-Hungarians. Both the Russian Imperial general staff and the Central Powers regarded the area as a sideshow in view of the massive confusion in the wake of the Gorlice–Tarnów Offensive and the subsequent Russian retreat.

However, the Russian commander in Gnizediu became determined to hold his position upon opening a map and discovering that the city was the last portion of Congress Poland still in Russian hands. Accordingly, he disobeyed the order to retreat and was left at the head of a narrow salient. Scholars contend that the commander, a minor noble, was convinced that his actions would result in greater opportunities after the war. His abilities, and those of his troops, were not up to the task.

Within a week after Central Powers troops entering the area, Gnizediu was cut off from reinforcements after Austro-Hungarian troops crossed the river on barges downstream. The Russian commander, perhaps seeking to inspire his troops, beheaded the emissary sent to request a surrender. This act irritated the besiegers enough that they brought up heavy artillery from operations further west. Gnizediu was subsequently bombarded into rubble.

The Russians eventually mutinied, executed their commander, and attempted to withdraw to the east. Only a handful of troops were able to break through the blockade. While the operation is almost forgotten today, it is notable for the fact that it incurred the highest percentage of Russian casualties (98.5% of the defenders) and the heaviest artillery bombardment (equivalent to two days’ shelling at Verdun) in four years of combat on the Eastern Front.