Expansion of the frontiers.—Having exploded for the time being some of the notions of great wonders in the far distant interior, the Spanish pioneers fell back on the established frontiers, and by a more gradual and rational process extended them northward, much as the English a century later slowly pushed their settlements from the Atlantic shoreline across the Tidewater and up into the Piedmont.
On the Atlantic seaboard Spanish outposts were advanced from the West Indies into what are now Florida, Georgia, South Carolina, and, momentarily, into Virginia. In Mexico, missions, mines, farms, and stock ranches advanced northward in regular succession or side by side. Between the return of Coronado and the end of the century the frontiers of actual occupation moved forward, roughly speaking, from Guadalajara, Querétaro, and Pánuco, to a line drawn irregularly through the mouth of the Rio Grande westward to the Pacific, with many large spaces, of course, left vacant to be filled in by subsequent advances. The Spanish pioneers, like those of England and France, recorded their home attachments by the place names given their new abodes, and thus the whole northern district of Mexico was comprised within the three provinces of New Galicia, New Vizcaya, and New León. During the same period the Philippine Islands had been occupied as an outpost of Mexico.
The Adelantados.—The latter sixteenth century was still within the age of the adelantados, when the development of the Spanish frontiers was left largely to men of means, obligated to bear most of the expense of conquering and peopling the wilderness, in return for wide powers, extravagant titles, and extensive economic privileges. As types of these proprietary conquerors of the period there stand out Ibarra in Nueva Vizcaya, Menéndez in Florida, Legazpi in the Philippines, Carabajal in Nuevo León, and Oñate in New Mexico. The period likewise was still within the age of the encomienda, when the right to parcel out the natives was inherent in the privilege of conquest. With the turn of the century the custom practically ceased, a fact which sharply distinguishes Florida and New Mexico from the later frontier Spanish provinces of Texas, California, and Louisiana.
A new spirit.—The age of wanton bloodshed, too, had largely passed. The New Laws, promulgated in 1543, stood for a new spirit, and royal authority had by now become somewhat established on the frontiers. In proportion as the encomenderos were discredited for their abuses and as their power over the Indians was checked, a larger and larger place was found on the frontier for the missionaries, to whom passed much of the actual work of subduing and controlling the natives.
THE MINES OF NORTHERN MEXICO
Audiencia and diocese of Nueva Galicia.—In 1544 Compostela became the seat of the new diocese of Nueva Galicia. Four years later the new Audiencia of Nueva Galicia was established there. About 1550 Guadalajara became the seat of both jurisdictions, and the judicial and ecclesiastical capital of all the country to the north and northeast, a position which it long occupied. The Audiencia district was subdivided into corregimientos, each under an alcalde, subject to the Audiencia. Within the corregimientos were Indian partidos, each under a native alcalde, subject to the encomenderos or the missionaries.
The Zacatecas mines.—In spite of the check caused by the Mixton War, northward expansion in Mexico was soon stimulated by the discovery of rich mines, and by the ambitions of the new viceroy. Mines developed in southern Nueva Galicia were soon eclipsed by those of Zacatecas, which were opened in 1548 by Juan de Tolosa, Cristóbal de Oñate, Diego de Ibarra, and Baltasar Treviño. These men soon became the richest in America, and Zacatecas the first mining town in New Spain. The fame of the "diggins" spread, and other parts of the country were for a time nearly depopulated by the rush of miners.
Francisco de Ibarra.—Inspired by the "boom" at Zacatecas, the Audiencia of Nueva Galicia planned to subdue the districts of Sinaloa and Durango. Ginés Vázquez de Mercado, sent for this purpose in 1552, wasted his energies in a fruitless search for a fabled mountain of pure silver, and was defeated by the Indians near Sombrerete. Martin Pérez, sent by the Audiencia to the same district in 1558, came into conflict with Francisco de Ibarra, agent of the viceroy. In 1554 Ibarra began a series of explorations by means of which, in the course of eight years, he and his men opened in northern Zacatecas the mines of San Martin, San Lucas, Sombrerete, Chalchuites, Aviño, Fresnillo, and other places. To make these expeditions, he equipped himself at his own or his uncle's expense with soldiers, horses, Negro slaves, Indian servants, and droves of stock for food. He attracted miners and settlers by furnishing them with outfits and by giving them free use of mineral deposits.
Nueva Vizcaya founded.—In 1558 Velasco planned to send Ibarra northward to pacify a region called Copala, but his departure was delayed by the sending of the De Luna expedition to Florida. In 1562 Ibarra was made governor and captain-general of a new province called Nueva Vizcaya, comprising the unconquered districts beyond Nueva Galicia, to which Zacatecas remained attached. In the following year he founded Nombre de Diós and Durango, the latter of which became and long remained the military capital of all the northern country. In the same year Rodrigo del Rio de Losa was sent with soldiers and miners to open the mines of Indé, and of Santa Barbara and San Juan in southern Chihuahua. The shortage of Indian labor in the mines there resulted by 1580 in slave hunting raids down the Conchos River and across the Rio Grande into modern Texas.
Ibarra on the Pacific slope.—Amid extreme hardships in 1564 Ibarra crossed the mountains to the westward, and conquered Topia, which he had hoped would prove to be "another Mexico." Disappointed in this, he spent two or three years in developing Sinaloa. Beyond Culiacán, on the Río Fuerte (then called Río Sinaloa) he founded the Villa of San Juan. From here with new recruits from Mexico and Guadalajara, in June, 1567, he set out northward. Ascending the Yaqui valley, at Zaguaripa he defeated the very Indians who had destroyed Coronado's town of San Gerónimo. Crossing the sierra eastward, he emerged on the plains at the river and ruined pueblo of Paquimé (Casas Grandes) in northern Chihuahua. Turning back along the eastern slope of the Sierras, he recrossed them, with terrible hardship, into the lower Yaqui valley. Returning to Chiametla, he died about 1570, after twenty years of exploring, mining, colonizing, and administration. He was one, of the ablest of the second generation of colonizers in New Spain.