Tomás Villalba y Albin (9 December 1805 – 12 July 1886) was a Uruguayan politician who served as interim President for five days (15 February to 20 February 1865), at the end of the Uruguayan War, which had begun on 10 August 1864. The war was fought between the governing Blanco Party and the Colorado Party, with the latter supported openly by the Empire of Brazil and covertly by the Argentine president, Bartolomé Mitre. The Uruguayan War was part an almost continuous struggle between the Blanco and Colorado factions since Uruguayan independence in 1828, and was closely linked to a wider regional conflict involving Argentina, Brazil, Paraguay and Uruguay which culminated in the Paraguayan War (also known as the War of the Triple Alliance). The Colorado leader Venancio Flores started a rebellion in 1863 to overthrow Blanco President Bernardo Berro, who led a coalition Colorado–Blanco government. After a series of battles, the Colorados and the Brazilian army controlled most of the country, with the Blancos left in control of just the capital, Montevideo. On March 1, 1864, President Berro stepped down and was replaced by a hard-line senator, Atanasio Aguirre.