 Complete the following phrase:  During the PolishLithuanian Commonwealth, the Zaporizhian Cossack state was allied to the Catholic King of Poland, and the Cossacks were often hired as mercenaries. That had a strong impact on the Ukrainian language and led to the establishment of a functioning Ukrainian Greek Catholic Church in 1596 at the Union of Brest. The Ukrainians, however, retained their Orthodox Christian faith and Cyrillic alphabet. During the 