Spanish interest in the territory known as New Mexico increased during the 1580s and 1590s because of mining and missionary possibilities and King Phillip II of Spain’s concern about rival English exploration in the New World. In 1595, Don Juan de Onate was commissioned to lead an expedition to claim and colonize the New Mexico region for the king. After many delays, Onate and his party of 400 men and members of their families left Santa Barbara, Mexico, in January 1598. Rather than follow earlier routes, they crossed the Chihuahua desert to reach the El Paso area. On April 30, 1598, at this site, Onate issued La Toma, a proclamation taking possession of the region for Spain, including all land drained by the Rio del Norte, the Rio Grande. Proceeding north, he established headquarters near present Santa Fe and founded the province of New Mexico. As governor, he directed exploration of the area until resigning in 1607. Onate’s expedition and La Toma brought Spanish rule to the American Southwest and preceded colonization efforts of other European nations on the North American continent.