DIAZ, Roy, Spanish soldier, born in Seville, Spain, in 1503; died in Peru, 26 April 1538. He went to Peru with the expedition of Diego de Almagro in 1532, and as captain took part in the conquest of the interior of the country, and the capture of Cuzco, 1534. In the same year he was assigned to the command of Sebastian Velalcazar in his conquest of the province of Quito, where he became prominent by his daring shown in the numerous bloody encounters with the troops of the cacique Ruminahui. While reconnoitering, he was surrounded by a large number of Indians, and, notwithstanding his valiant defense, would have been crushed had he not at the critical moment slain the principal chief in the midst of his followers, whereupon the enemy fled. and ever afterward they retreated before the Spanish troops when they saw Diaz. In the same year, being in the advance guard with Vasco Guevarra and three soldiers, he was surrounded and furiously attacked by Indians, and only by a desperate fight succeeded in saving himself and joining the main army. When Velalcazar tried to discover the hiding place of the immense treasure that Rumifiahui was said to possess, this cacique, by skilful movements, evaded the Spanish attack; but while he was on the march to surprise Quite, Diaz, with sixty cavalrymen, overtook and engaged him till Velalcazar with his force and his allies, the Cufiari Indians, could come up, and routed him with great loss, so that Ruminahui took refuge in the ¥umbo mountains, abandoning his train with a part of the treasure.

When the province of Quite was invaded, in March 1534, by the forces of Pedro Alvarado from Guatemala, A1magro, by order of Pizarro, marched with Velalcazar's forces to defend the territory in July but, desiring to avoid strife between Spanish forces, he sent Ruy Diaz with Bartolome de Segovia and Diego Aguero to make pacific proposals to Alvarado, and Diaz obtained a settlement, signed by A1magro and Alvarado, 26 August by which Alvarado turned over his forces to Almagro and returned to Guatemala. When Pizarro resolved to build near the coast a City destined to be the capital of the Spanish possessions in Peru, he sent an expedition under Diaz to explore the territory of the cacique of the valley of the Rimac, and Diaz, finding the country fertile and well adapted for the purpose, made a favorable report to Pizarro, who ordered a City to be built on the spot designated by Diaz, and on 18 January 1535, the foundation stone of the City of Los Reyes (now Lima) was laid. When the dissension between Pizarro and A lmagro concerning the boundary of their respective governments began, Diaz was in that City, and, as a follower of Ahnagro, sustained the governor, Hernando de Soto. On the departure of Almagro for his expedition to Chili in 1535, he ordered Diaz to go to Lima to recruit soldiers, and follow him with these forces.

Diaz soon joined Ahnagro with his troops, and participated in the campaign in Chili. On the latter's return in the beginning of 1537, he, wishing to establish an alliance with Manco Inca, who had risen against Pizarro, sent Ruy Diaz with other officers as envoy to the Indian prince, who, regarding all Spaniards as his natural enemies, retained the commissioners as prisoners, tied them naked to a stake, painted and pelted them with fruit and mud, subjected them to all kinds of indignities, and forced them to drink large quantities of the Indian intoxicating liquor, chicha. Almagro, once in possession of Cuzco, 18 April 1537, began hostilities against Manco Inca. During the obstinate and relentless warfare that Orgonez waged against Manco Inca till the final destruction of his hosts, Diaz took advantage of a favorable opportunity to escape, and joined Orgonez's forces. He continued to fight for Ahnagro against Pizarro's attack, and was present at the victory of Abancay, 12 July 1537, the advance to Chincha in September and the retreat to Cuzco in November. In the unfortunate battle of Salinas, 26 April 1538, Diaz was in command of the escort bearing the royal standard, and, after the defeat of Almagro's forces, Ruy Diaz was overtaken in his flight by Pizarro's soldiers, and killed.