A military coup in Argentina ousts Ramón Castillo.

The 1943 Argentine Revolution was a coup d'état on 4 June 1943 that ended the government of Ramón Castillo, who had been fraudulently elected to the office of vice-president before succeeding to the presidency in 1942 as part of the period known as the Infamous Decade. The coup d'état was launched by the lodge "United Officers' Group" (GOU), a secret military organization of nationalist nature. Although its soldiers shared different views of nationalism: there were Catholic nationalists, Radicals, military with a more pragmatic approach, and even fascists. The military was opposed to Governor Robustiano Patrón Costas, Castillo's hand-picked successor, a major landowner in Salta Province and a primary stockholder in the sugar industry. The only serious resistance to the military coup came from the Argentine Navy, which confronted the advancing army columns at the Navy Petty-Officers School of Mechanics.