The Wikipedia article of the day for March 30, 2017 is Juan Manuel de Rosas.
Juan Manuel de Rosas (30 March 1793 – 14 March 1877) was an army officer who ruled Buenos Aires Province and briefly the Argentine Confederation. Like other wealthy provincial warlords, Rosas enlisted rural workers from his landholdings in a private militia, and took part in the numerous disputes and civil wars in his country. He eventually became the undisputed leader of the Argentine army and the Federalist Party. In 1831, he signed the Federal Pact, recognizing provincial autonomy and creating the Argentine Confederation. He established a dictatorship and formed the repressive Mazorca, an armed parapolice that killed thousands of citizens. By 1848, after a war against the Peru–Bolivian Confederation, a blockade by France, and a revolt in his own province, he ruled all of Argentina, and was attempting to annex the neighboring nations of Uruguay and Paraguay. When the Empire of Brazil came to Uruguay's aid, Rosas declared war in August 1851. The short Platine War ended with the defeat of Rosas and his flight to Britain. His last years were spent in exile living as a tenant farmer.