The German occupation of Czechoslovakia was the final concession of the policy of appeasement. Hitler's pacts with Italy and the Soviet Union gave him the confidence to invade Poland. This act led Britain to declare war.
On 15 March 1939, German troops marched into Czechoslovakia. They took over Bohemia, and established a protectorate over Slovakia.
Hitler's invasion of Czechoslovakia was the end of appeasement for several reasons:
Greater Germany(the Czechs were not Germans)
The takeover of Czechoslovakia in March 1939, allowed Germany to strengthen.
The German invasion of Czechoslovakia in March 1939 brought an end to Neville Chamberlain's appeasement policy. Chamberlain offered to help Poland if it was attacked by Germany, and the British public now faced full scale preparations for war.