It was unlikely that an invasion would ever have a peaceful ending, especially one marked by impossible alliances. The Spanish conquest of the Aztec Empire ultimately ended in victory but at a bloody cost for all involved.

The fall of the Mexica or Aztec Empire in 1521 is tied to some of the most brutal episodes of the conquest of the New World. One name stands out beyond Hernán Cortés himself: Pedro de Alvarado.

Alvarado, the right-hand man of the humble Extremaduran nobleman who had transformed into one of Spain’s leading explorers, was known among the indigenous people as “el Sol” (“the Sun”) or “Tonatiuh” in Nahuatl.

Alvarado’s distinctive wavy blond hair and towering height made the indigenous people mistake him for a god, an illusion that would not last long as his actions revealed his true nature as a ruthless and ambitious conqueror.

Feared even by his own troops, Pedro de Alvarado was a strong yet merciless leader. His ambition and brutality shaped his legacy, leaving behind a trail of bloodshed that contributed to the downfall of the Mexica Empire.

His actions led to two pivotal massacres: the slaughter of indigenous nobles at the Tóxcatl festival and the Spanish forces’ disastrous retreat during La Noche Triste, marking the beginning of the end for the Mexica.

Moctezuma Is Arrested

On November 8, 1519, Cortés entered the Mexica capital and met Emperor Moctezuma.

Around the same time, letters arrived from Villa Rica de la Vera Cruz informing him that Juan de Escalante, the captain Cortés had left in charge of Veracruz, had been killed along with six of his officers at the hands of the Mexicas.

Six days after the Spaniards reached Tenochtitlán, under the pretext of avenging their fallen men, they took Moctezuma prisoner.

At dawn, Cortés and five of his captains—Pedro de Alvarado, Gonzalo de Sandoval, Juan Velázquez de León, Francisco de Lugo, and Alonso de Ávila—along with their two translators, armed themselves and set out for the emperor’s palace.

Through his translator, Doña Marina, Cortés accused Moctezuma of attacking his allies and demanded an explanation. He ordered the emperor to accompany him to his father’s palace, where Spanish soldiers would guard him.

Moctezuma protested, insisting he had not given such orders and that he would immediately send captains to investigate the matter. However, realizing he would be detained regardless, he ultimately complied.

Moctezuma was shackled from the first day of his imprisonment.

The chronicler Chimalpahin describes the scene: “As soon as the Spaniards arrived in Mexico, despite facing no resistance, they ordered Moteuhczomatzin to be bound and imprisoned, locking him in his own home and placing irons on his feet.

The same fate befell his brother Cacamatzin of Texcoco and Itzcuauhtzin, the military leader of Tlatilulco.”

Despite his captivity, Moctezuma lacked nothing. He was still allowed to receive visits from his subjects and continued to be served by his attendants and concubines. Yet, many of his nobles and military leaders disapproved of this Spanish maneuver.

The emperor urged his people to remain calm, warning that uprisings in Tenochtitlán could only make things worse. But the situation would soon spiral out of control.

The Tóxcatl Massacre

Among the most sacred dates in the Mexica calendar was the Tóxcatl festival, a celebration of drought that honored the gods Huitzilopochtli, Tláloc, and Tezcatlipoca in hopes of bringing rain to fertilize the land.

Held between May and June, the festival was a time of peace—warfare was strictly forbidden. Instead, the people adorned themselves with their finest jewels and garments, sang, played music, and danced in reverence.

In May 1520, as preparations for Tóxcatl were underway, Hernán Cortés was forced to leave Tenochtitlán to confront Pánfilo de Narváez, another Spanish explorer sent to Mexico with orders to arrest Cortés and put an end to his unauthorized conquests.

In Cortés’ absence, command of the Spanish forces in Tenochtitlán fell to Pedro de Alvarado.

Alvarado had two primary responsibilities: to guard Moctezuma II—who had been confined, under the guise of friendship, in the former palace of his father, Axayácatl, now a Spanish stronghold—and to maintain peace among the Mexica people, who were growing increasingly uneasy about whether the Spaniards were allies or conquerors.

However, for reasons still debated by historians, Alvarado ordered an attack on the indigenous people during their most sacred festival, slaughtering the assembled Aztec nobility and all who attended the celebration.

The Massacre at the Templo Mayor

As the festival was in full swing and the courtyard of the Templo Mayor overflowed with people singing and dancing, Spanish forces, alongside their Totonac and Tlaxcalan allies, launched a surprise attack.

Men, women, and children were mercilessly slaughtered.

Blood flooded the temple grounds as Alvarado and his men looted the jewelry from their victims.

Mexica codices recount the horror. Some were struck from behind, their entrails spilling to the ground. Others had their heads split open… Some tried to flee, dragging their intestines, stumbling over them as they ran.

The ruthless massacre shocked and outraged the Mexica people, igniting an irreversible rebellion.

The Uprising and Moctezuma’s Death

For the first time since the arrival of the Spaniards, the Aztecs took up arms against them.

The fighting was fierce, forcing the Spanish to retreat into their palace-turned-fortress. The Mexica besieged the Spanish garrison, even attempting to burn it down—even though Moctezuma remained inside.

Upon returning to Tenochtitlán, Cortés ordered Moctezuma to pacify his people. However, the emperor was now seen as a traitor. When he appeared on a rooftop to speak to his subjects, they pelted him with stones and arrows, fatally wounding him.

Spanish accounts claim he died from these wounds, while indigenous sources insist he was already dead—murdered by the Spaniards—before being displayed to the crowd.

La Noche Triste: The Sorrowful Night

For a month, the Spaniards were trapped, facing dwindling supplies and no way out. The Mexicas had dismantled the bridges, preventing escape. Cortés eventually ordered a desperate retreat—carrying as much Aztec gold as possible.

On the rainy night of June 30, 1520, under cover of darkness, the Spanish forces attempted to flee. But as they crossed a makeshift bridge, they were discovered. In moments, thousands of Mexica warriors surrounded them.

The lake around Tenochtitlán was filled with canoes carrying native warriors.

Arrows rained down. The retreat turned into a massacre. Hundreds of Spaniards and their allies were slain, their bodies sinking into the lake—many drowned by the weight of the very gold they had stolen.

By dawn, over 600 Spaniards and countless Tlaxcaltecas had perished. The survivors fled toward Tlaxcala, regrouping for the final assault that would, a year later, bring the Mexica Empire to an end.