The conquest of Mexico began on the sea, in 1519, when Hernán Cortés set sail for the mainland. Governor Diego Velázquez had first approved the expedition, then changed his mind and withdrew his support. Cortés ignored the order. He gathered men and horses at Trinidad, and finally set out with roughly eleven ships, five hundred soldiers, and thirteen horses.

When he landed at Tabasco in February, the Aztec emperor Montezuma II invited him to the capital, Tenochtitlan. The emperor half-believed Cortés might be the feathered serpent god Quetzalcoatl, whose return the old prophecies seemed to place in that very year. So he received the Spanish as honored guests, unaware that Cortés had spent the journey building alliances with local peoples who resented Aztec rule. Once inside the city, Cortés seized the emperor and held him hostage.

With Montezuma in chains, the Spanish raided a capital of more than 140,000 inhabitants. But no conquest proceeds in a straight line. While Cortés was inside Tenochtitlan, word arrived that another Spanish force had come from Cuba under Pánfilo de Narváez, sent by Governor Velázquez to arrest Cortés for launching an unauthorized invasion. Determined not to be stopped, Cortés left the city temporarily to confront Narváez directly.

He placed Pedro de Alvarado in command with a few hundred soldiers, a mix of Spaniards and Tlaxcaltecs, and ordered him to hold Tenochtitlan until his return. Alvarado chose a violent course of action. He ordered a massacre of many Aztec leaders, and the city erupted in fury. When Cortés came back, he found his position untenable.

The Aztecs counterattacked with a ferocity that overwhelmed the Spanish. During the chaos, Montezuma was killed, though the circumstances remain disputed. The Spanish suffered terrible losses that wiped out much of what they had gained. In a single night, later known as the Noche Triste, the Night of Sorrows, roughly half of Cortés’s men perished trying to escape the city.

The survivors were wounded, exhausted, and stripped of their artillery. Their gunpowder was nearly gone. They fled to friendly Tlaxcala, grateful simply to find shelter. The newly installed Aztec emperor, Cuitláhuac, showed no mercy.

He gathered as many soldiers as he could and sent a large army under his brother Matlatzincatzin to finish the Spanish off. The remnants of Cortés’s force met the Aztec army in the Valley of Otumba around July 7, 1520. The Aztecs heavily outnumbered the Spanish. Early in the battle, they seemed to be winning.

Cortés held his ground and devised a dangerous plan. He spotted Matlatzincatzin and his commanders by their brightly colored regalia. Gathering his best horsemen, including Alonso de Ávila, Cristóbal de Olid, Juan de Salamanca, Pablo de Sandoval, and Pedro de Alvarado, he launched a sudden charge straight at the Aztec leadership. The shock of the attack broke the Aztec command.

Matlatzincatzin stumbled, and Juan de Salamanca knocked him down with his lance. With their commander fallen, the Aztec army scattered. The Spanish survived, but they had learned how near they had come to absolute ruin. The independence struggle that eventually ended Spanish rule followed a different road.

For three centuries after the fall of Tenochtitlan, Mexico had been New Spain, a colony ruled from Madrid. In 1808, Napoleon invaded Spain, toppled the Spanish monarchy, and threw the empire into chaos. Across the colonies, questions of loyalty and authority surfaced. In Mexico, resentment against the colonial system had been building for years, and the moment now seemed ripe for change.

On September 16, 1810, a parish priest named Miguel Hidalgo y Costilla issued his famous call for rebellion, the Grito de Dolores, which rallied Mexicans to take up arms against their Spanish rulers. Hidalgo’s movement grew quickly, and his forces captured several towns as they marched toward the capital. But at Calderón, in January 1811, his hopes were crushed. He and his rebels were defeated while trying to seize Mexico City.

Hidalgo attempted to escape north toward the United States, but he was captured. Stripped of his priestly status, he was executed by firing squad. The rebellion he had ignited, however, did not die with him. Another revolutionary priest, José María Morelos y Pavón, took up the cause.

Soon he was joined by Agustín de Iturbide, a former royalist general, and by rebel leaders such as Vicente Guerrero. The war dragged on for years, neither side able to deliver a final blow. Then, in 1820, a liberal government came to power in Spain and offered reforms intended to calm the colony. Conservative factions in New Spain saw this as a threat to their interests, and they began to shift toward independence themselves.

In 1821, Iturbide and Guerrero issued the Plan of Iguala. It called for an independent Mexico with a constitutional monarchy, the Catholic Church as the established faith, and official equality between Spanish-born and Mexico-born Spaniards. Notably, the plan promised no such equality to Indigenous people or those of mixed ancestry. Most royalist forces that still resisted the revolution were defeated, leaving Viceroy Juan de O’Donojú with little choice.

Lacking the troops and resources to fight, he signed the Treaty of Córdoba on August 24, 1821, recognizing Mexico’s independence and establishing a constitutional monarchy. When no Bourbon prince could be found to take the throne, Iturbide was crowned Agustín I, the first emperor of Mexico. His reign was short. Antonio López de Santa Anna, working alongside Guadalupe Victoria, overthrew the emperor and drafted a new constitution that turned the empire into a federal republic of nineteen states and four territories.

Guadalupe Victoria became the first president. Santa Anna became a general and earned lasting fame at the siege of the Alamo in 1836 during the Texas War of Independence. His Mexican forces triumphed at the Alamo, though Texas secured its independence later that same year, a fact Mexico would not officially accept for years. The dispute over Texas eventually helped trigger the Mexican-American War, which cost Mexico not only Texas but also California and the Southwest.

Santa Anna later served as president of Mexico on multiple occasions. He was exiled repeatedly, each time managing to return, and he died in 1876, having come back to Mexico shortly before his death. By then, the country had endured a brief French occupation, which ended in 1867. In the 1870s, Porfirio Díaz rose to power as a divisive new president.

His dictatorship led directly to the Mexican Revolution of 1910, a civil war that cost the lives of around two million people. Only in 1934, under the administration of Lázaro Cárdenas, did Mexico finally find the stability and the foundations for progress. In the years since, despite continuing conflicts and challenges, Mexico has stood as a fully independent nation and a founding member of the United Nations.