Russian occupation of Eastern Galicia (1914–1915)
On August 18, 1914, the Russian Empire invaded the Austrian Crownland of Galicia. On August 19, the Imperial Russian Army defeated the Austro-Hungarian Army, advanced 280–300 kilometers into the territory of Austria-Hungary and captured most of eastern Galicia.
Source: Wikipedia — Russian occupation of Eastern Galicia (1914–1915) (CC BY-SA 4.0)