Predecessors , 1936. In February 1942, German and Italian submarines began targeting Brazilian ships in the Atlantic Ocean. This was influenced by Brazil's adherence to the Atlantic Charter, which mandated automatic alignment with any American continent nation attacked by a foreign power. Brazil's gradual alignment with the United States was significant for its government, especially in light of German and Italian attempts to interfere in Brazilian internal affairs. The implementation of the
Estado Novo made it increasingly difficult to maintain stable trade relations with these countries, particularly due to British and later US naval pressure. An element of this pressure was President
Franklin D. Roosevelt's Good Neighbor policy, which included economic and commercial incentives such as financing the construction of the
Companhia Siderúrgica Nacional (CSN). Reports at the time stated that the United States had planned to invade the northeast of Brazil (
Plan Rubber) if
Getúlio Vargas insisted on maintaining Brazil's neutrality. In 1942, following the US proposal to finance the CSN, US forces established airbases along Brazil's North-Northeast coast. The most notable of these was at
Natal, near
Parnamirim, in the state of
Rio Grande do Norte, known as the "Trampoline of Victory" ("
Trampolim da Vitória" in Portuguese). This base played a crucial role in the Allied war effort, particularly before the Allied landing in North Africa in November 1942 in
Operation Torch. With the stabilization of the Italian front and the diminishing German submarine threat by late 1943, the US bases in Brazil were gradually deactivated in 1944–45. However, the US maintained a presence on
Fernando de Noronha until 1960. The frequency of attacks increased markedly after Brazil severed diplomatic relations with the Axis powers on January 28, 1942. The situation escalated dramatically in August 1942, when six ships were sunk within just two days, causing over 600 casualties. This surge in attacks prompted Brazil to officially declare war on the Axis on August 22, 1942. In 1943, despite significant enhancements in patrolling and anti-submarine warfare measures through joint Brazilian and US operations, Axis submarines continued their assaults in the South Atlantic, particularly off the coasts of
São Paulo and
Rio de Janeiro. The majority of the targeted vessels were merchant or mixed cargo and passenger ships, primarily belonging to major shipping companies such as
Lloyd Brasileiro, Lloyd Nacional, and Costeira. Smaller shipping companies and regional shipowners were also affected, as well as vessels owned by regional shipowners and seafarers, including the barge
Jacira and the fishing boat
Shangri-lá. Lloyd Brasileiro, the largest of these companies, suffered the greatest losses, with 21 of its ships attacked, and 19 sunk. The Brazilian Navy lost three warships in World War II: •
Vital de Oliveira: An auxiliary ship torpedoed by
U-861 on July 19, 1944, while en route to Rio de Janeiro after stops in the Northeast and Espírito Santo. It was the last Brazilian ship to be torpedoed in the war; •
Camaquã: A corvette that capsized in a storm on July 21, 1944, resulting in the deaths of 23 crew members; To secure this area, the Allies began establishing bases in Brazil in mid-June 1941. Task Force No. 3 arrived, and the ports of
Recife and
Salvador were prepared for use by the
US Navy. In response, the Axis powers sought to obstruct the shipment of raw materials to the United States and the United Kingdom, leading to attacks on merchant ships navigating the Atlantic. ==Pre-entry attacks==