When World War II started, Zagreb was the capital of the newly formed autonomous Banovina of Croatia within the Kingdom of Yugoslavia, which remained neutral in the first years of the war. After the Invasion of Yugoslavia by Germany and Italy on 6 April 1941, German troops entered Zagreb on 10 April. On the same day, Slavko Kvaternik, a prominent member of the Ustaše movement, proclaimed the creation of the Independent State of Croatia (NDH), an Axis puppet state, with Zagreb as its capital. Ante Pavelić was proclaimed Poglavnik of the NDH and Zagreb became the center of the Main Ustaša Headquarters, the Government of the NDH, and other political and military institutions, as well as the police and intelligence services.