Graduated from the Colegio Militar.
During the Chaco War (1932-1935), Busch was one of the few genuine Bolivian military heroes to emerge from the conflict. By the end of the war, he was a colonel.
Colonel Busch as a leader of a group of young officers who seized power from the conservative civilian government in June 1936, a few months after the end of the Chaco War. Although the new president. Colonel David Toro, proclaimed his regime to be “socialist,” nationalized the Standard Oil Company’s concessions, and for the first time established a Ministry of Labor, some of its original military and civilian supporters became disillusioned in the Toro government.
In July 1937 President Toro was ousted in a coup led by Germán Busch, who was proclaimed president.
Busch had associated with him a number of leftist civilians. One was Gustavo Navarro, better known by his pseudonym Tristan Marof, whose followers were particularly active in organizing the miners. Another was a young lawyer and economist, Víctor Paz Estenssoro, who drew up what was probably the most important decree of the Busch regime. This required the Big Three tin mining companies to sell to the Bolivian Central Bank all foreign exchange they earned and to buy from the bank whatever foreign currency they needed to conduct their business or repatriate profits. The mining firms strongly objected to this decree, the first serious limitation on their freedom of operation in Bolivia.
About two and a half months after the issuance of thу decree, President Busch died. The official explanation was that he had commited suicide, although many associated with his regime insisted that he had been killed. In any case, his death ended the short period of post-Chaco War military reformism. After the victory of the Nationalist Revolutionary Movement (MNR), headed by his one-time minister Paz Estenssoro, Busch was pictured as a precursor of the Bolivian National Revolution.