Although Christopher Columbus and the generation of explorers who followed him had discovered a new world in America, their dreams of riches had eluded them. In Spain’s new Caribbean island colonies both gold and native workers, who had mostly died from European diseases, were scarce. A new wave of adventurers, among them Hernán Cortés, a minor nobleman from the poor Spanish province of Extremadura, turned their vision toward new fabled empires—perhaps even the elusive Cathay—beyond the setting sun. In Cuba, Cortés patched together a motley force of 550 men, an assortment of small ships, a few horses and cannons and sailed west in early 1519. By the time they landed on Mexico’s Gulf Coast on April 22, 1519, Cortés’s men, torn by dissension and realizing the impossible odds against them, were near mutiny.
Cortés, however, cut his losses and exploited his opportunities with extraordinary aplomb. He won over the doubters, isolated the dissenters, and ended any thoughts of retreat to Cuba by burning his ships. Next he capitalized on the lucky coincidence that he had landed on the Mexican coastline in the Aztec year of Ce Acatl, exactly the same 52-year cyclical anniversary year in which Quetzalcoatl-Topiltzín had vowed to return from the east to reclaim his kingdom.
As he led his band of adventurers westward over the mountains toward the Aztec capital of Tenochtitlán, Cortés played Quetzalcoatl to the hilt, awing local leaders. Coaxed by Doña Marina, his wily native translator-mistress-confidante, local chiefs began to add their armies to Cortés’s march against their Aztec oppressors.
A few months later, inside the gates of Tenochtitlán, the Venice-like island metropolis, it was the Spaniards’ turn to be awed: by gardens full of animals, gold, and palaces, and a great pyramid-enclosed square where tens of thousands of people bartered goods gathered from all over the empire. Tenochtitlán, with perhaps a quarter of a million people, was the great capital of an empire as large and rich as any in Europe.
Moctezuma II, the lord of that empire, fearing that Cortés was in fact the god Quetzalcoatl incarnate, had followed Cortés’s progress toward Tenochtitlán with trepidation. Wishing not to offend, Moctezuma II had sent Cortés sumptuous gifts of gold, coupled with warnings to stay away. Encouraged by the gold, Cortés demanded an early audience with the emperor, who pathetically surrendered himself to Cortés’s custody and “donated” his entire empire to the Spanish crown.
With his position temporarily secure, Cortés dispatched emissaries west, east, and south. To Oaxaca he sent Hernando Pizarro and Diego de Ordaz, each with small detachments, to reconnoiter for riches. Pizarro searched for gold in the Papaloapaon basin around Tuxtepec and later the Chinantla, while Ordaz passed through the Mixtec kingdoms of Yanhuitlán and Sosola on his way to the Gulf Coast.
Meanwhile, however, the people of Tenochtitlán were rioting against Spanish brutality. On July 1, 1520, with Moctezuma II mortally wounded by his own countrymen, Cortés and his men, forced by the sheer numbers of rebellious Mexicans, retreated, hacking a bloody path through thousands of screaming Aztec warriors to safety on the lakeshore.
Hearing the news of Cortés’s defeat, Mexican garrisons in Oaxaca dealt a similar blow against the local Spanish expeditions, attacking and killing dozens of Spaniards and their indigenous allies.
Although Cortés was down, he wasn’t out. In succeeding months, as his forces regathered strength in the Valley of Mexico, he pushed the conquest of the south. Alonso de Avila arrived in Oaxaca in late 1520 and accepted the ambassadors of Zapotec kings Cosijoeza and Cosijopí, who were more than willing to ally themselves against their Aztec overlords. Concurrently, other Spanish expeditions thrust into Oaxaca: Gonzalo de Sandoval successfully counterattacked against the Aztec garrisons, while Juan Cedeño obtained the submission of the Chinantecs and the northern Zapotecs.
In late 1521, reinforced by fresh soldiers, horses, a small fleet of armed sailboats, and 100,000 indigenous allies, Cortés retook Tenochtitlán. The stubborn defenders, led by Cuauhtémoc, Moctezuma’s nephew, fell by the tens of thousands beneath a smoking hail of Spanish grapeshot. The Aztecs, although weakened by smallpox, refused to surrender. Cortés found, to his dismay, that he had to destroy the city in order to take it.
Soon after Cortés’s triumph, the Zapotec kings Cosijoeza and Cosijopí sent ambassadors declaring their submission to him and his king, Charles V. This alarmed the Mixtecs, who, with the backing of the Chinantec king of Tuxtepec, declared war on the Zapotecs. At the request of his new Zapotec allies, Cortés dispatched Francisco de Orozco in December 1521 and Pedro de Alvarado a month later with a few hundred infantry and a handful of cavalry to pacify Oaxaca. After a few skirmishes, Orozco took possession of Huaxyacac, the site of present-day Oaxaca City , which the Aztec garrisons had occupied since 1456. A few hours later, on the same day, December 25, 1521, padre Juan Díaz celebrated the first Catholic mass in Oaxaca territory. A month later at the same spot, Alvarado, with the help of padre Bartolomé de Olmedo, helped negotiate a peace agreement between the Mixtecs and Zapotecs.
With the valley and northern Oaxaca pacified, Cortés sent Alvarado to conquer the Oaxacan Pacific coast. On March 4, 1522, Alvarado defeated Casandoo, the Mixtec king of Tututepec , and with colonists displaced from the Valley of Oaxaca  by Cortés’s orders, he founded the Villa Segura de la Frontera (Secure Village of the Frontier). He went on to pacify the whole coast, including Tonameca, Pochutla, Huatulco , and Astata, all the way east to Tehuántepec.