Slavs
Slavs can be further grouped by religion. Orthodox Christianity is practiced by the majority of Slavs. The Orthodox Slavs include the Belarusians, Bulgarians, Macedonians, Montenegrins, Russians, Serbs, and Ukrainians and are defined by Orthodox customs and Cyrillic script as well as their cultural connection to the Byzantine Empire (Serbs also use Latin script on equal terms). Their second most common religion is Roman Catholicism. The Catholic Slavs include Croats, Czechs, Kashubs, Moravians, Poles, Silesians, Slovaks, Slovenes, and Sorbs and are defined by their Latinate influence and heritage and connection to Western Europe. There are also substantial Protestant and Lutheran minorities especially amongst the West Slavs, such as the historical Bohemian (Czech) Hussites.
Russians in Ukraine
Following the dissolution of the Soviet Union, Ukraine became an independent state. This independence was supported by the referendum in all regions of Ukrainian SSR, including those with large Russian populations. A study of the National Academy of Sciences of Ukraine found that in 1991, 75% of ethnic Russians in Ukraine no longer identified themselves with the Russian nation. In the December 1991 Ukrainian independence referendum 55% of the ethnic Russians in Ukraine voted for independence.