Juan Manuel José Domingo Ortiz de Rosas y López de Osornio (born Juan Manuel Ortiz de Rozas, 1793-1877) was a conservative Argentinian politician who ruled Argentina from 1829 to 1852. Rosas was one of the first of famous caudillos in Latin America.

Rosas came on to the national scene as a powerful cattle rancher. He controlled the cattle frontier pampa of Argentina, allowing him rule over the capital, Buenos Aires. Rosas defeated the European expeditionary forces in 1820 with the help of gauchos.

In 1829, Rosas became governor of Buenos Aires. In subsequent years, Rosas went in and out of power over this period but remained a strong leader. During his years out of office (1832-1835) Rosas fought to gain territory from the indigenous population in southern Argentina.

As a conservative leader, Rosas portrayed himself as a man of the people who could relate to the working class of gauchos and African Americans. Rosas used his man of the people ideal to unify Argentina during his era. Rosas supporters called themselves Rosistas. Rosas rule was filled with violence -- he killed his opponents and anyone who would not support him. As Charles Darwin related in The Voyage of the Beagle, he met Rosas who was then engaged in exterminating tribes of wandering horse-mounted Indians, describing him as a man of extraordinary character, a perfect horseman who conformed to the dress and habits of the Gauchos and "obtained an unbounded popularity in the country, and in consequence a despotic power". Darwin included a story of how Rosas had himself put in the stocks for inadvertently breaking his own rule of not wearing knives on Sundays. This appealed to his men's sense of egalitarianism and justice.

Rosas's portrait appears on the 20 Argentine Peso bill

Rosas attempted to reincorporate Uruguay and Paraguay as Argentinean provinces and this led to two European blockades of Buenos Aires. During Rosas' rule, the Falkland Islands were invaded by England. Rosas wanted to rid Argentina of European influence and cultivate a feeling of nationalism among Argentinians.

Rosas' opponents during his rule were liberals such as Juan Bautista Alberdi, Bartolomé Mitre, and Domingo Faustino Sarmiento. Rosas liberal opponents were exiled to other countries such as Uruguay and Chile.

In 1852 Rosas was overthrown by Justo José de Urquiza under the support of Uruguay and Brazil; his army was defeated at Monte Caseros. Rosas spent the rest of his life in exile in England as a farmer in Southampton.

See also

History of Argentina