Pedro de Mendoza

In 1529, he offered to explore South America at his own expense and establish colonies. Thanks to the efforts of his relative María de Mendoza, wife of Secretary of State [[Francisco de los Cobos]], in 1534 his offer was accepted: he was made ''adelantado'' [[governorate|governor]], [[captain general]], and [[chief justice]] over [[Governorate of New Andalusia|New Andalusia]]. This grant allowed him authority over as much land as he could conquer, within 200 [[league (unit)#Spain|leagues]] of the southern limit of [[New Toledo]]. Although this was measured along the Pacific coast, it was understood that his efforts would be directed towards the [[Río de la Plata]] on the Atlantic. The Emperor gave Mendoza 2000 men and 13 ships on the condition that within two years Mendoza should transport 1000 colonists, build roads into the interior, and construct three forts. He was to have half the treasure of the [[Cacique|chiefs]] killed and nine-tenths of the ransom.{{citationneeded|date=December 2025}} The office of Governor was also, in theory, made hereditary.{{how|date=December 2025}}{{citationneeded|date=December 2025}}

In 1529, he offered to explore South America at his own expense and establish colonies. Thanks to the efforts of his relative María de Mendoza, wife of Secretary of State [[Francisco de los Cobos]], in 1534 his offer was accepted: he was made ''adelantado'' [[governorate|governor]], [[captain general]], and [[chief justice]] over [[Governorate of New Andalusia|New Andalusia]]. This grant allowed him authority over as much land as he could conquer, within 200 [[league (unit)#Spain|leagues]] of the southern limit of [[New Toledo]]. Although this was measured along the Pacific coast, it was understood that his efforts would be directed towards the [[Río de la Plata]] on the Atlantic. The Emperor gave Mendoza 2000 men and 13 ships on the condition that within two years Mendoza should transport 1000 colonists, build roads into the interior, and construct three forts. He was to have half the treasure of the [[Cacique|chiefs]] killed and nine-tenths of the ransom.{{citationneeded|date=December 2025}} The office of Governor was also, in theory, made hereditary.{{how|date=December 2025}}{{citationneeded|date=December 2025}}

That year, he set sail with a considerable fleet, but a terrible storm scattered it off the coast of Brazil. Here his lieutenant, Juan de Osorio, was assassinated, according to some authorities by the orders of Mendoza himself because of suspected disloyalty.{{fact|date=September 2025}} Mendoza sailed up the Río de la Plata in 1535 and established himself on what would later become (and is said to be by most Argentinian historians) "Parque Lezama" in [[Buenos Aires]] on 2 February 1536, after being confronted by the indigenous people the small fort he established was burnt.{{fact|date=September 2025}}

That year, he set sail with a considerable fleet, but a terrible storm scattered it off the coast of Brazil. Here his lieutenant, Juan de Osorio, was assassinated, according to some authorities by the orders of Mendoza himself because of suspected disloyalty.{{fact|date=September 2025}} Mendoza sailed up the Río de la Plata in 1535 and founded [[Buenos Aires]] on 2 February 1536.{{fact|date=September 2025}}

Mendoza was not a very effective leader because he was debilitated by a severe case of syphilis. He spent half of his time ill in bed, but he put as much effort as he could into the expedition. No notable campaigns occurred in the River Plate during this time, and the only chronicler was a German soldier named [[Ulderico Schmidt]] (or Ulrico Schmidl). Schmidt came over to the River Plate with Don Pedro and stayed there for eighteen years, fighting in almost every battle. His account of this early history of the River Plate region is the most important document from that time period.

Mendoza was not a very effective leader because he was debilitated by a severe case of syphilis. He spent half of his time ill in bed, but he put as much effort as he could into the expedition. No notable campaigns occurred in the River Plate during this time, and the only chronicler was a German soldier named [[Ulderico Schmidt]] (or Ulrico Schmidl). Schmidt came over to the River Plate with Don Pedro and stayed there for eighteen years, fighting in almost every battle. His account of this early history of the River Plate region is the most important document from that time period.