Przemysl was a major fortified city on the Austro-Hungarian border with Russia, north of the Carpathian Mountains. In 1914 it had recently been modified. Its defences were similar to those of similar places in Western Europe, with a circuit of modern forts surrounding the city. At the start of the war, Przemysl was used to support the Austro-Hungarian armies as they launched their first invasion of Russian Poland. The Austrian Fourth Army had moved north from Przemysl, defeating the Russian Fifth Army at the battle of Komarow (26 August-1 September 1914).
The Austrian offensive soon ended in failure and retreat. By mid-September Austrian troops were streaming south past Przemysl towards the Carpathians, where a new Austrian line would soon be formed. One army corps joined the garrison of Przemysl within the defences of the fortress, a total of 150,000 men.
The first part of the siege began on 24 September, when the Russians cut off the last route out. The Russians did not have the same strength in heavy artillery as the Germans or Austrians, and the siege developed into a lengthy blockade.
The first phase of the siege was short lived. October 1914 saw a German attack on Warsaw, which forced the Russians to withdraw troops from the Carpathian front. This allowed the Austrians to advance back towards their original border, and on 11 October the siege was lifted. The last action of the first siege was a costly Russian assault that failed to threaten the city.
This would be a short lived reprieve. The German attack on Warsaw failed, and the Austrians were once again forced to retreat back towards the Carpathians. The siege was renewed on 9 November, this time by the Russian Eleventh Army. This time there were 110,000 Austro-Hungarian troops in the fortress, with enough supplies for three months.
The fate of Przemysl was decided by the failure of the Austro-Hungarian winter offensive of 1915. One minor aim of this offensive had been the relief of Przemysl, while the wider aims including a massive pincer operation in coordination with the Germans in East Prussia that would result in the capture of all of Russian Poland. Neither objective succeeded.
Once it was clear that the relief effort had failed, the Austrians launched a final sortie from Przemysl, and then on 22 March surrendered. 2,500 officers, 117,000 men and 1,000 guns were captured by the Russians.
The Russians were soon forced back out of Przemysl. A combined German-Austrian offensive ended with the great victory of Gorlice-Tarnów, which forced the Russians to abandon the entire Polish salient. On 3 June, less than three months after it had surrendered, the Austrians recaptured Przemysl.