Gualberto Villarroel assumed office as the 39th President of Bolivia on 20 December 1943, and his term was violently cut short by his death on 21 July 1946.

A colonel during the Chaco War, Villarroel and the Reason for the Fatherland (RADEPA) military lodge joined the fledgling Revolutionary Nationalist Movement (MNR) to overthrow President Enrique Peñaranda in a coup d'état.

On 20 December 1943, members of the RADEPA young officers clique, in conjunction with MNR militants, overthrew the conservative government of President Enrique Peñaranda.

[8] The distrust came as a result of U.S. participation in World War II and the erroneous belief (sparked by President Peñaranda in order to persecute political opponents)[9] that the MNR was pro-Nazi and pro-Axis.

These tensions peaked when a tripartite group of workers, students, and teachers threatened to strike if wages were not raised and the MNR stayed in government.

[17] The situation spiralled out of control when the MNR Minister of Agriculture Julio Zuazo Cuenca was among a group of government officials who drunkenly smashed the windows of the Higher University of San Andrés.