 They were heavily clustered in the entire mountainous periphery of Czechoslovakia—not only in the former Moravian "Provinz Sudetenland" but also along the northwestern Bohemian borderlands with German Lower Silesia, Saxony and Bavaria, in an area formerly called German Bohemia.In total the German minority population of pre-World War II Czechoslovakia numbered around 20% of the total national population.Sparking a "Sudeten Crisis", Hitler got his future enemies to concede the "Sudetenland" with most of the Czechoslovak border fortifications in the 1938 Munich Agreement, leaving the remainder of Czechoslovakia shorn of its natural borders and buffer zone, finally occupied by Germany in March 1939.