Brazilian Navy in World War II

The Brazilian Navy participated in World War II in the Battle of the Atlantic, from Brazil's entry into the war in 1942 until its end in 1945. Its campaign consisted of defending maritime traffic against German and Italian submarines, in conjunction with the Brazilian Air Force and the United States Armed Forces, with the latter exercising operational command in the South Atlantic. Its main activities included escorting convoys between Rio de Janeiro and Trinidad in the Caribbean, with additional missions such as escorting the Brazilian Expeditionary Force on its way to Europe.

Submarine attacks against the Brazilian merchant navy were the immediate factor in Brazil's entry into the war and threatened the supply of raw materials to the Allies and the provisioning of major coastal cities. The pre-war Brazilian fleet, consisting mostly of remnants of the Fleet of 1910, was unprepared for anti-submarine warfare. Naval strategists were, until then, more concerned with a regional war between surface forces. A naval program outlined in 1932 reactivated, albeit with difficulty, the construction of warships on national soil. During the war, the adaptation of existing ships, the incorporation, through Lend-Lease, of sixteen submarine chasers (the G and J classes) and eight escort destroyers (the Bertioga class), and training on new equipment created a fleet geared towards anti-submarine warfare, with small but modern ships.

Two task forces were organized: the Northeastern Naval Force (FNNE) and the Southern Patrol Group (GPS), operating respectively north and south of Rio de Janeiro, with other resources assigned to the Naval Commands on the coast. Brazilian Marines garrisoned several ports and Trindade Island. With the combined Allied effort, the submarine threat was almost suppressed by the end of 1943. The Brazilian Navy convoyed 3,164 ships, of which 99.01% reached their destinations. Three ships and 486 military personnel were lost in operation. No enemy submarines were directly sunk by the Brazilian Navy; aviation, which it lacked, was the main destroyer of submarines in operations. Brazilian naval participation in hunter-killer missions would only begin in the final stage of the war.

In the post-war period, the Brazilian Navy aligned itself with the United States in the acquisition of ships and joint preparation for anti-submarine warfare, with Soviet submarines replacing German ones in Cold War naval thinking. A divergence on both points would occur a few decades later. The navy's institutional historical narrative on the conflict opposes the view that only focuses on the Brazilian Army and blames political neglect for the state of unpreparedness and improvisation in which the country found itself.