From 1935 to 1939, Germany and Italy escalated their demands for territorial gains and greater influence in world affairs. Italy invaded Ethiopia in 1935, resulting in condemnation by the League of Nations and widespread diplomatic isolation. In 1936, Germany remilitarized the industrial Rhineland, a region that had been ordered demilitarized by the Treaty of Versailles. In 1938, Germany annexed Austria and the Sudetenland region of Czechoslovakia. The next year, Czechoslovakia was partitioned between Germany and a client state of Slovakia. At the same time, from 1938 to 1939, Italy was demanding territorial and colonial concessions from France and Britain in the Mediterranean. In 1939, Germany prepared for war with Poland, but also attempted to gain territorial concessions from Poland through diplomatic means. Germany demanded that Poland accept the annexation of the Free City of Danzig to Germany and authorize the construction of automobile highways from Germany through the Polish Corridor into Danzig and East Prussia, promising a twenty-five-year non-aggression pact in exchange. The Polish government did not trust Hitler's promises and refused to accept German demands. Following a strategic alliance between Germany and the Soviet Union in August 1939, the two powers invaded Poland in September of that year.