The Battle and Fall of Przemysl was a 1915 documentary war film shot on the Eastern Front by official war photographer to the Central Powers, Albert K. Dawson. Its four reels depicted the Siege of Przemyśl, disastrous for the Austrians, with incidents reenacted using soldiers as extras. Most of it has been lost.
References
The Battle and Fall of Przemysl Wikipedia(Text) CC BY-SA