[1] Born in the Val-de-Cães neighbourhood in Belém on June 2, 1888, to Major Marcelino Cardoso Barata and Gabrina de Magalhães Barata, Joaquim spent most of his childhood in the city of Monte Alegre, Pará, enlisted in the military in 1904 and graduated from the military school of Realengo on Rio de Janeiro in 1911 to become an Aspirant in the Brazilian Army.

[1] After graduation, Magalhães Barata was sent to the 47th Hunter Battalion in his hometown of Belém, where he was promoted to second lieutenant in 1915 and given command of the garrison in the city of Oiapoque in the border with French Guiana.

[1] In December 1931, Magalhães Barata founded the Liberal Party of Pará, which reunited the revolutionary elements in the state and supported the politics of Getúlio Vargas, being affiliated with his National Civic Union.

[1][2] In January 1936, Magalhães Barata returned to active military service, assuming command of the 6th Hunter Battalion in Ipameri, in May of the same year, was promoted to lieutenant colonel and in September 1939 was promoted to colonel remaining in military service until February 8, 1943, when he was once again nominated Federal Interventor in the State of Pará where he remained until the end of the Vargas Government.

[1][3] As a senator, Magalhães Barata was a member of the Constitutional Commission, the Commission of the Armed Forces and the Subcomission of National Security, in 1947, he supported Major Luís Geolás de Moura Carvalho in the state elections for the state of Pará, which Moura Carvalho won, defeating General Alexandre Zacarias de Assunção.

[1] In 1954, Magalhães Barata got reelected as senator and in 1955 with the support of Juscelino Kubitschek he defeated Epílogo de Campos by 1743 votes and was elected governor of Pará, a position which he held until his death on May 29, 1959, at 70 years of age.