People of Burundi annually celebrate Independence Day on July 1. On this day Belgian colony Ruanda-Urundi split to form Rwanda and present-day Burundi.
Colonization of Burundi began in the early 20th century by Germany. The territories of Burundi and Rwanda were occupied by Belgium during World War I and after the end of the war they became a Belgian League of Nations mandate territory. Belgium administered both countries as one colonial empire, known as Ruanda-Urundi.