Pereira was born in Santiago de Cuba. He had degrees in Chemistry and Pharmacy from the University of Madrid. In 1905 he became professor of chemistry in the University of Salamanca. He founded Acción Republicana with Manuel Azaña. During the dictatorship of Miguel Primo de Rivera he conspired against the regime, and was imprisoned three times. When the Second Republic was declared, he was named director of the Universidad Complutense de Madrid and advisor of State. Between 1931 and 1933 he served as Minister of the Navy.
After the failure of Diego Martínez Barrio to form a government to restrain the military revolt of 17 July 1936, Azaña ordered Giral to form a new government constituted exclusively by republicans. This 133rd Prime Minister government lasted from 19 July to 4 September 1936. Then, with the fall of Talavera de la Reina and the Army of Morocco within reach of Madrid, Giral was forced to cede power to Francisco Largo Caballero.
After the end of the Spanish Civil War he went to France, then to Mexico. In 1945 he succeeded Juan Negrín as prime minister of the Spanish Republican government in Exile until 1947. He died in Mexico.
He married María Luisa González y de la Calle.
|Premier||19 July 1936||4 September 1936||José Giral||Republican Left|
|State (Foreign Affairs)||19 July 1936||4 September 1936||Augusto Barcía Trelles||Republican Left|
|Justice||19 July 1936||4 September 1936||Manuel Blasco Garzón|
|War||19 July 1936||6 August 1936||General Luis Castello Pantoja|
|6 August 1936||4 September 1936||Juan Hernández Saravia|
|Navy||19 July 1936||22 August 1936||José Giral||Republican Left|
|22 August 1936||4 September 1936||Francisco Maíz Sánchez|
|Interior||19 July 1936||4 September 1936||General Sebastián Pozas Perea|
|Finance||19 July 1936||4 September 1936||Enrique Ramos Ramos||Republican Left|
|Industry and Commerce||19 July 1936||4 September 1936||Plácido Álvarez-Buylla Lozana||Republican Union|
|Communications and Merchant Marine||19 July 1936||4 September 1936||Bernardo Giner de los Ríos||Republican Union|
|Public Works||19 July 1936||4 September 1936||Antonio Velao Oñate||Republican Left|
|Agriculture||19 July 1939||4 September 1936||Mariano Ruiz-Funes García|
|Education and Fine Arts||19 July 1936||4 September 1936||Francisco Barnés Salinas|
|Labor, Health and Planning||19 July 1936||4 September 1936||Juan Lluhí|
Diego Martínez Barrio
|Prime Minister of Spain
Francisco Largo Caballero
- Beevor, Antony (2006). The Battle for Spain: the Spanish Civil War, 1936-1939. New York: Penguin Books. ISBN 0-14-303765-X.
- Pike, David Wingeate (2011). France Divided: The French and the Civil War in Spain. Sussex Academic Press. ISBN 978-1-84519-490-1. Retrieved 2015-08-27.
- Urquijo y Goitia, José Ramón de (2008). Gobiernos y ministros españoles en la edad contemporánea. Editorial CSIC - CSIC Press. ISBN 978-84-00-08737-1. Retrieved 2015-08-27.