Czech Silesia (České Slezsko) is one of the three Czech lands and a section of the Silesian historical region. It is located in the north-east of the Czech Republic, predominantly in Moravian-Silesian Region, with a section in northern Olomouc Region. Also known as Moravian Silesia (Moravské Slezsko or Moravskoslezsko), it mostly belonged to Austrian Silesia before 1918; between 1938 and 1945 area was also named Sudeten Silesia, referring to the Sudetenland.