When the president of Brazil resigned in August 1961, he was lawfully succeeded by João Goulart, the democratically elected vice president of the country. João Goulart was a proponent of democratic rights, the legalization of the Communist Party, and economic and land reforms, but the US government insisted that he impose a program of economic austerity. The United States government implemented a plan with the code name Operation Brother Sam for the destabilization of Brazil, by cutting off aid to the Brazilian government, providing aid to state governors of Brazil who opposed the new president, and encouraging senior Brazilian military officers to seize power and to back army chief of staff General Humberto de Alencar Castelo Branco as coup leader. General Branco led the April 1964 overthrow of the constitutional government of President João Goulart and was installed as first president of the military regime, immediately declaring a state of siege and arresting more than 50,000 political opponents within the first month of seizing power, while the US government expressed approval and re-instituted aid and investment in the country.