The Aztec Empire | The Triple Alliance

The Aztec Empire dominated Central America for two hundred years. By the time the Europeans arrived in 1517, the empire stretched from coast to coast. It controlled central Mexico and outlying regions.

History of the Aztec Empire

To understand the Aztec Empire, it helps to go back to its beginnings. It started with the Mexica people, later called the Aztecs, who remained one of the most powerful groups throughout the empire’s history. The Mexica were nomads. But when they arrived in Central Mexico, other migratory peoples had already claimed the best land.

Undaunted, the Mexica worked as mercenaries for a lesser king, Culhuacan. Their agreement with Culhuacan soon fell apart, and the Mexica were cast out as wanderers again. They came across Lake Texcoco, where, according to legend, they saw an eagle perched on top of a cactus. Taking this as a sign, they built artificial islands in the lake and established their city, Tenochtitlan, in 1325.

The Mexica were successful farmers and warriors. One hundred years later, they went to war against the nearby Tepanec kingdom and recruited the support of several other cities. After winning the war, they formed the famous Triple Alliance with two of these cities, Texcoco and Tlacopan. They divided the Tepanec lands among each other, creating the Aztec empire.

The Triple Alliance expanded over the next hundred years until they ruled 5 to 6 million people. Although each city originally had equal power, Tenochtitlan soon emerged as the dominating force. It was the largest city by far in Mesoamerica, totaling over 140,000 citizens.

Map of maximum expansion of the Aztec Empire

Map of maximum expansion of the Aztec Empire

Structure and Government

At the empire’s height, it governed 500 small states. This system was similar in some respects to the Greek city-states. The Aztecs did not claim sovereign authority over all these states; instead, they insisted that the states pay regular tribute.

The Aztecs allowed their tributary states to keep their local governments, which were similar across the empire and had existed long before the Aztecs. The families of each city organized into groups called the calpulli. The leaders of the calpulli formed the city council, which had four executive members. One of the executive members was also the tlatoani, the king of the city.

The Triple Alliance cities also governed themselves with this structure. Since Tenochtitlan was the capital, its city council ruled the empire. The tlatoani of Tenechtitlan was called the Huey Tlatoani, or the Great Speaker.

This system was not only efficient, but it also kept the city-states satisfied and less likely to revolt. The Aztec rule is called an informal government or a hegemony. It often resulted in the Aztecs taking control of pockets of land, so the empire was rarely one unified mass.


The city of Texcoco codified the most advanced code of laws. This code was strict and judged offenders by evidence rather than their social status. The Texcocans recorded 80 distinct laws.

Tenochtitlan also had a set of written laws, although historians know less about it. Religion played a key role in it: several of the laws, like not running through the streets naked, had a moral basis. Theft and murder were also severely punished. Their judicial system was advanced, as it had several layers. Those who were disappointed with the outcome of their case in a provincial court could appeal to a higher, appellate court. The Huey Tlatoani had final authority in the most extreme cases.


The emperor of the Aztec empire, or Huey Tlatoani, ruled by divine right. Like in Egypt and Rome, the Aztecs believed that the Huey Tlatoani represented the gods and should be worshiped. Yet, the king did not inherit the throne, although family lines were important. Modern historians are unsure exactly how this process occurred, but there was a semi-democratic element, since the Huey Tlatoani was elected from the Tinochtitlan council.

The first emperor of the Triple Alliance was Itzcoatl, although four kings had already ruled in Tinochtitlan before him. Under Itzcoatl, the Aztecs defeated the Tepanecs and instituted their own kingdom. The second emperor was Moctezuma I, who established and reformed the empire during a time of peace. His rule was responsible for creating the Aztec government and society.

The most famous Aztec emperor was Moctezuma II. During his reign (which was full of war), the empire reached the height of its size and power. But in 1520, the early Spanish invaders killed Moctezuma II. Intriguingly, the surviving accounts of Moctezuma II's personality and rule are all different. As a result, it is almost impossible to determine any facts about him.

Depiction of the Coronation of Montezuma I

Coronation of Montezuma I


The Aztec empire had three main resources. Of course, they received tribute from the city-states. But they were also an agricultural society. The Aztecs were excellent farmers, and their crops provided food for the cities. In addition to tribute and agriculture, they supported their economy with trade.

Aztec markets were grand affairs. The biggest one in Tlatelolco attracted 60,000 people every day. Those who had money could purchase almost anything imaginable. The traders were a respected social class called the pochteca. They traveled throughout the empire, collecting luxury items for the nobility.


The Aztecs expanded their empire through warfare. They had an efficient and powerful army that they organized by ranks. Each rank had different colors of armor and different weapons. The lowest ranking soldiers only had a club and shield, but the highest ranks carried obsidian-tipped spears. Other weapons included bows and arrows, blowguns, slings, axes, and daggers.

The most important accomplishment of a soldier was capturing enemy soldiers, who were killed as human sacrifices. Soldiers who captured many enemy warriors were awarded higher ranks. They even had uniforms that indicated how many warriors they had captured. The highest societies for commoners were the Eagle and Jaguar Knights. The nobility had an even higher society, the Shorn Ones, who shaved their heads and went first into battle.

Tlatoani during war time

Tlatoani during war time

Spanish Conquest

The Spaniards first came to Mexico from Cuba in 1517. Their reports encouraged the governor of Cuba, Diego Velasquez, to send a small army to Mexico under the command of Hernan Cortes. This began the Spanish Conquest of the Aztec Empire. Cortes found a bilingual slave woman, Malinche, to translate for him. He learned about the Aztecs and encountered cities that wanted to revolt against their rule.

Cortes founded a city, Veracruz, and trained his soldiers into an elite army. He then marched to Tenochtitlan, where the Aztecs received him hospitably. But Cortes took Moctezuma II and the nobility hostage. Moctezuma II died during this time, although it is unclear how. His son took the throne and drove out the Spaniards.

Cortes regrouped and formed alliances with enemies of the Aztecs. In 1521, he defeated Tinochtitlan. About 240,000 people died during the invasion, and Cortes razed the city to the ground. He rebuilt it as Mexico City, and the dominion of the Aztec Empire was over.

Facts about the Aztec Empire

  • It was founded by the Mexica people in 1325 AD.
  • Three cities (Tenochtitlan, Texcoco, and Tlacopan) called the Triple Alliance ruled the empire.
  • The most powerful city was Tenochtitlan.
  • The empire was made up of city-states that paid tribute to the Triple Alliance.
  • Each city had a council, the calpulli, and a leader, the tlatoani.
  • The cities had written laws and judicial courts.
  • The emperor was called the Huey Tlatoani (the Great Speaker).
  • The first emperor was Itzcoatl, who defeated the Tepanecs and formed the Triple Alliance.
  • The most famous emperor was Moctezuma II, who was ruling when the Spaniards arrived.
  • Aztec economy was based on tribute, agriculture, and trade.
  • The empire expanded by warfare.
  • Soldiers advanced up the ranks by capturing enemy warriors for human sacrifice.
  • The Spanish army under Hernan Cortez defeated the Aztecs in 1521 AD.