Abstract is: The Czechs (Czech: Češi, pronounced [ˈtʃɛʃɪ]; singular Czech, masculine: Čech [ˈtʃɛx], singular feminine: Češka [ˈtʃɛʃka]), or the Czech people (Český lid), are a West Slavic ethnic group and a nation native to the Czech Republic in Central Europe, who share a common ancestry, culture, history, and the Czech language. Ethnic Czechs were called Bohemians in English until the early 20th century, referring to the former name of their country, Bohemia, which in turn was adapted from the late Iron Age tribe of Celtic Boii. During the Migration Period, West Slavic tribes settled in the area, "assimilated the remaining Celtic and Germanic populations", and formed a principality in the 9th century, which was initially part of Great Moravia, in form of Duchy of Bohemia and later Kingdom of Bohemia, the predecessors of the modern republic. The Czech diaspora is found in notable numbers in the United States, Canada, Israel, Austria, Germany, Slovakia, Ukraine, Switzerland, Italy, the United Kingdom, Australia, France, Russia, Argentina, Romania and Brazil, among others.