German Bohemians (German: Deutschböhmen und Deutschmährer [ˈdɔʏtʃˌbøːmən] ; Czech: čeští Němci a moravští Němci, lit. 'German Bohemians and German Moravians'), later known as Sudeten Germans (German: Sudetendeutsche [zuˈdeːtn̩ˌdɔʏtʃə] ; Czech: sudetští Němci), were ethnic Germans living in the Czech lands of the Bohemian Crown, which later became an integral part of Czechoslovakia. Before 1945, over three million German Bohemians constituted about 23% of the population of the whole country and about 29.5% of the population of Bohemia and Moravia. Ethnic Germans migrated into the Kingdom of Bohemia, an electoral territory of the Holy Roman Empire, from the 11th century, mostly in the border regions of what was later called the "Sudetenland", which was named after the Sudeten Mountains.
The process of German expansion was known as Ostsiedlung ("Settling of the East"). The name "Sudeten Germans" was adopted during rising nationalism after the fall of Austria-Hungary in the aftermath of First World War. After the Munich Agreement (1938), the so-called Sudetenland became part of Germany.
