Wikipedia (excerpts): Upon the outbreak of World War I, the name Ukraine was used only geographically, as the term did not exist nationally. The territory that made up the modern country of Ukraine was part of the Russian Empire with a notable southwestern region administered by Austro-Hungarian Empire, and the border dating to the Congress of Vienna in 1815. By 1914, Ukrainian nationalism had matured to a point where it could significantly influence the future of the region. As a result of this nationalism and of the other main sources of Russo-Austrian confrontations, including Polish and Romanian lands, both empires eventually lost these disputed territories when these territories formed new, independent states. The Russian advance into Galicia began in August 1914. During the offensive, the Russian army successfully pushed the Austrians right up to the Carpathian ridge effectively capturing all of the lowland territory, and fulfiling their long aspirations of annexing the territory. Ukrainians were split into two separate and opposing armies. 3.5 million fought with the Imperial Russian Army, while 250,000 fought for the Austro-Hungarian Army. Many Ukrainians thus ended up fighting each other. Also, many Ukrainian civilians suffered as armies shot and killed them after accusing them of collaborating with opposing armies (see Ukrainian Austrian internment). During World War I the western Ukrainian people were situated between Austria-Hungary and Russia. Ukrainian villages were regularly destroyed in the crossfire. Ukrainians could be found participating on both sides of the conflict. In Galicia, over twenty thousand Ukrainians who were suspected of being sympathetic to Russian interests were arrested and placed in Austrian concentration camps, both in Talerhof, Styria and in Terezín fortress (now in the Czech Republic).