Answer:
Germany annexed the Sudetenland prior to WWII.
Step-by-step explanation:
For many centuries prior to World War One, the Sudetenland was part of Bohemia, an area inhabited mostly by Czhechs. This region was located in the Archduchy of Austria, later the Austrian Empire, and after that the Austro-Hungarian Empire. The Sudetenland at the time was called German Bohemia, and it was on the outer edges of the region of Bohemia. After Austria-Hungary's dissolution, the area was awarded to the new nation of Czechoslovakia as the Entente wanted to seek it as an ally. In the 1930s, Germany, under the Nazis, expanded its territory. It annexed Austria in 1938, then the Sudetenland in 1939, followed by the rest of Czechoslovakia soon after. Its invasion of Poland began the Second World War.
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