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.
South Slavs
The Proto-Slavic homeland is the area of Slavic settlement in Central and Eastern Europe during the first millennium AD, with its precise location debated by archaeologists, ethnographers and historians. None of the proposed homelands reaches the Volga River in the east, over the Dinaric Alps in the southwest or the Balkan Mountains in the south, or past Bohemia in the west. Traditionally, scholars put it in the marshes of Ukraine, alternatively between the Bug and the Dnieper, however, according to F. Curta, the homeland of the southern Slavs mentioned by 6th-century writers was just north of the Lower Danube. Little is known about the Slavs before the 5th century, when they began spreading in all directions.