Fearing an invasion by the Axis Powers, Regent Prince Paul signed the Tripartite Pact on 25 March 1941, pledging cooperation with the Axis. Massive [anti-Axis] demonstrations followed in Belgrade. On 27 March, the regime of Prince Paul was overthrown by a military coup d'état with British support. The 17-year-old Peter II was declared to be of age and placed in power. General Dušan Simović became his Prime Minister. The Kingdom of Yugoslavia withdrew its support for the Axis de facto without formally renouncing the Tripartite Pact. Although the new rulers opposed Nazi Germany, they also feared that if German dictator Adolf Hitler attacked Yugoslavia, the United Kingdom was not in any real position to help. Regardless of this, on 6 April 1941, the German armed forces (Wehrmacht) launched th