Any member of the most numerous ethnic and linguistic body of peoples in Europe. They live chiefly in eastern and southeastern Europe but also extend across northern Asia to the Pacific. Slavs are customarily subdivided into eastern Slavs (Russians, Ukrainians, and Belarusians), western Slavs (Poles, Czechs, Slovaks, and Wends, or Sorbs), and southern Slavs (Serbs, Croats, Bulgarians, Slovenes, and Macedonians). Historically, western Slavs were integrated into western Europe; their societies developed along the lines of other western European nations. Eastern and southern Slavs suffered Mongol and Turkish invasions and evolved more autocratic, state-centred forms of government. Religion (mainly Eastern Orthodoxy and Roman Catholicism) divides Slavs, as does the use of the Cyrillic and Latin alphabets. In the Middle Ages, Slavic polities that left a rich cultural heritage developed in Bohemia, Poland, Croatia, Bosnia, Serbia, and Bulgaria, but, by the end of the 18th century, all these states had been absorbed by powerful neighbours (the Ottoman Empire, Austria, Hungary, Prussia, Russia). Eastern Slavic history often was marked by unsuccessful attempts to repel Asian invaders. In the 16th century, Muscovy (later Russia) embarked on a course of expansion across northern and central Asia that eventually made it the most powerful Slavic state. Pan-Slavism in the 19th century had some influence on the formation of the new Slavic states after World War I, though Czechoslovakia and Yugoslaviathe two attempts to integrate different Slavic peoples into single politieshad both disintegrated by the end of the 20th century, one peacefully and the other violently.