The First World War and the Russian Civil War led to the first massive political emigration, which strengthened the existing Ukrainian communities by infusing them with members from political, scientific, and cultural backgrounds. Furthermore, some of these new emigrants formed Ukrainian communities in Western and Central Europe. Thus, new communities were created in Czechoslovakia, Germany, Poland, France, Belgium, Austria, Romania, and Yugoslavia. The largest was in Prague, which was considered one of the centres of Ukrainian culture and political life (after Lviv and Kraków).