In the eighteenth century a number of Irish noblemen governed large areas of South America through appointment by the Spanish king. Ambrosio O'Higgins, who was born in Ballinary County Sligo in 1720, was appointed Viceroy of Peru in 1795, where he was known as 'the great viceroy'. Among his many achievements was the abolition of slavery in his viceroyalty. In the 1770s the king of Spain appointed Don Hugo O'Connor to reorganize the Spanish settlements in Texas which he did by ordering any Spanish settlers in the province to abandon the Nacogdoches area and concentrate on San Antonio.
In the next generation many South American countries came to regard Irish immigrants as founding fathers and national heroes. Bernardo O'Higgins, the son of Ambrosio, is known today as the 'Liberator of Chile', for the part he played in that country's independence war with Spain. William Brown who was born in Foxford County Mayo in 1777, is regarded as the founder of the Argentinian navy. Brown played a major role in first organizing Argentinian naval forces and then going on to successfully lead his ships in victorious wars in turn with the navies of Spain, Brazil and Uruguay. Admiral Brown returned to visit Ireland in 1847 where he hoped to meet realtions in County Mayo. He was reportedly very shocked by the famine conditions he encountered in the country. He died in 1857.
However, perhaps the most unusual figure was Eliza Lynch who was born in Cork in 1834. While in Paris she became the lover of the future Paraguayan dictator Francisco Solano López. From 1864-1870 López fought a devastating war with his neighbours Brazil, Argentina and Uruguay, known as the War of the Triple Alliance. Defeated by 1870 Eliza her husband and her children were cornered by Brazilian troops, with López and Eliza's eldest son Panchito being killed. Eliza spent the rest of her life in exile attempting to regain the riches she enjoyed while consort of the dictator of Paraguay. She is still a famous historical figure in that country.
These are just some of the most important figures but there are many, many more. Argentina even has a substantial proportion of its population of Irish descent, descended from Irish emigrants who arrived mostly in the second half of the nineteenth century.