ZALDÍVAR, JUAN DE (ca. 1570-1598). Juan de Zaldívar, Spanish soldier and explorer, was born on the mining frontier of northern Mexico about 1570. His parents were Vicente de Zaldívar, the elder, and Magdalena de Mendoza y Salazar. The Zaldívar and Oñate families of Zacatecas were charter members of a "silver aristocracy" that had discovered and developed mines at Zacatecas in the late 1540s. Over time, these families had entered into such complex marriage alliances that Juan de Oñate, the future colonizer of New Mexico, was both uncle and second cousin of Juan de Zaldívar and his brother, Vicente de Zaldívar, the younger. The Spanish crown granted Juan de Oñate a contract to settle New Mexico in September 1595, and he began the immediate recruitment of military officers and civilian settlers. The future governor chose his young kinsman, Juan de Zaldívar, as his maestre de campo and second in command. Circumstances beyond Oñate's control delayed final approval by the king's agent of preparations for the expedition until January 1598. From Santa Bárbara, situated near the headwaters of the Río Conchos in southern Chihuahua, Oñate's expedition advanced on a direct route to the Rio Grande, where it arrived, to the southeast of the site of modern Ciudad Juárez, on April 30. Continuing upriver, Oñate arrived at "El Paso," the ford in the river, on May 4. Accompanied by Juan de Zaldívar, Oñate spent several days on both banks of the river acquiring provisions and calming the fear of nearby Indians. By July 11 the Oñate colony had advanced up the Rio Grande to a site north of present Santa Fe, where its members established the first capital at San Juan de los Caballeros. On December 4, 1598, Juan de Zaldívar and twelve other Spaniards died in an Indian revolt atop the great rock at Acoma. The subsequent siege of the sky pueblo by Zaldívar's brother, the trial of the Acomas, and the drastic punishment inflicted upon them was prompted, at least in part, by a desire to avenge the death of Oñate's kinsman and maestre de campo.