Juan Manuel de Rosas (1793-1877) was an Argentine dictator. He was the prototype of the caudillo dictators of South America and ruled supreme in the Argentine Confederation from 1829 to 1852.

Juan Manuel de Rosas was born in Buenos Aires on March 30, 1793, and claimed descent from a noble Asturian family through Count Ortiz de Rosas. The first of his parents' 20 children, he detested school and spent most of his childhood on the family estancias, where he became one of the best horsemen in the Argentine and later excelled in all of the techniques of the gaucho frontiersman. His mediocre education led to his personal animosity toward his more highly educated contemporaries.

Rosas commenced his long military career at 15, when he volunteered in the Buenos Aires forces to combat the second English invasion of his homeland. This experience led him to mistrust the motives of any European powers dealing with his...