Rivera, Fructuoso (frōktō-ōˈsō rēvāˈrä) [key], 1790?–1854, first president of Uruguay (1830–34, 1839–42). After serving with Artigas, he was one of the Thirty-three Immortals who raised the standard of independence under Juan Antonio Lavalleja. He was chosen president and was responsible for the succession of Manuel Oribe, against whom he revolted in 1836. In the long civil strife, which was to characterize much of Uruguay's subsequent history, two factions appeared, distinguished by their badges, the Colorados [reds] of Rivera and the Blancos [whites] of Oribe. Rivera succeeded (1838) in routing Oribe, who fled to Buenos Aires. The following year Rivera declared war on Juan Manuel de Rosas, ruler of the United Provinces of La Plata (Argentina). With the help of Rosas, Oribe besieged Montevideo from 1843 to 1851. Rivera, opposed by factions within his own party, was exiled from the invested city in 1847, taking refuge in Brazil. After the downfall of Rosas and the end of the siege, he was selected (1853) as one of the triumvirate to head the provisional government of Uruguay.