DE ONATE, JUAN Juan de Oñate y Salazar (1550?-1626) was a Spanish conquistador who established the colony of New Mexico for Spain and became New Mexico's first governor. Oñate, the son of a conquistador who made a fortune in silver, was married to a granddaughter of Hernán Cortés. In 1595, Oñate requested that he be sent to conquer and rule New Mexico, search for treasure (especially the legendary silver treasure of Quivira), and bring Christianity to the local Indians. After governmental approval, Oñate left for New Mexico in January, 1598, with 400 settlers and soldiers (and their livestock). In July 1598, the expedition crossed the Rio Grande at El Paso. They arrived at the Tewa pueblo of San Juan and were helped by the local Indians. Oñate's group built San Gabriel, New Mexico's first capital. After they realized that the area was not rich in silver, many settlers wanted to return to Mexico, but Oñate would not let them go, and executed many of them. He was also incredibly brutal to the local Indians, killing, enslaving, and mutilating hundreds of Indian men, women, and children.

In 1601, Oñate led an expedition to the Great Plains of America that tried, unsuccessfully, to find the legendary silver of Quivira (thought to be in what is now central Kansas, east of Salina). While he was gone, most of his settlers returned to Mexico City. In 1604, he explored the area west toward the Colorado River and south to the Gulf of California. In 1606, Oñate made plans for the town of Santa Fé.

Later in 1606, Spain removed him from office (Don Pedro de Peralta was appointed to be the new governor); Oñate was later tried and found guilty of cruelty, immorality, mismanagement, dereliction of duties, and false reporting. Oñate was exiled from the colony. Later, on appeal, he was was cleared of the charges. Onate, sometimes called the "Last Conquistador," died in Spain in 1626.

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