Mexica Empire in the context of "Tetzcoco (altepetl)"

Moctezuma Xocoyotzin (c. 1466 – 29 June 1520), retroactively referred to in European sources as Moctezuma II, and often simply called Montezuma, was the ninth emperor of the Aztec Empire (also known as the Mexica Empire), reigning from 1502 or 1503 to 1520. Through his marriage with Queen Tlapalizquixochtzin of Ecatepec, one of his two wives, he was also the king consort of the altepetl.

The first contact between the indigenous civilizations of Mesoamerica and Europeans took place during his reign. He was killed during the initial stages of the Spanish conquest of the Aztec Empire when Hernán Cortés, the Spanish conquistador, and his men seized the Aztec capital of Tenochtitlan. During his reign, the Aztec Empire reached its greatest size. Through warfare, Moctezuma expanded the territory as far south as Xoconosco in Chiapas and the Isthmus of Tehuantepec, and incorporated the Zapotec and Yopi people into the empire. He changed the previous meritocratic system of social hierarchy and widened the divide between pipiltin (nobles) and macehualtin (commoners) by prohibiting commoners from working in the royal palaces.

The Mexica (Nahuatl: Mēxihcah [meːˈʃiʔkaḁ] ; singular Mēxihcātl) are a Nahuatl-speaking people of the Valley of Mexico who were the rulers of the Triple Alliance, more commonly referred to as the Aztec Empire. The Mexica established Tenochtitlan, a settlement on an island in Lake Texcoco, in 1325. A dissident group in Tenochtitlan separated and founded the settlement of Tlatelolco with its own dynastic lineage. In 1521, their empire was overthrown by an alliance of Spanish conquistadors and rival indigenous nations, most prominently the Tlaxcaltecs.

Today, descendants of the Mexica and other Aztec peoples are among the Nahua people of Mexico.

The Pipiltin (sg. pilli) were the noble social class in the Mexica Empire. They are the lowest nobles in the civilization's social structure and above the commoners who achieved noble status due to an outstanding deed in war. These people were members of the hereditary nobility and occupied positions in the government as ambassadors and ministers, the army and the priesthood. Pipiltin often headed their own noble houses, called tecalli, with their own lands and dependent labourers. The subclasses within the Pipiltin were: tlahtohcapilli (a tlahtoani's son), tecpilli or teucpilli (a teuctli's son), tlazohpilli (son of a legitimate wife), and calpanpilli (son of a concubine).

Children of the Pipiltin were given extensive education in preparation for the role they would play in their adult life. They were sent to the calmecac, which was the center for higher learning, to study the ancient wisdom as well as "elegant forms of speech, ancient hymns, poems and historical accounts, religious doctrines, the calendar, astronomy, astrology, legal precepts and the art of the government."

La Noche Triste ("The Night of Sorrows", literally "The Sad Night"), officially called in Mexico Victorious Night, was an important event during the Spanish conquest of the Mexica Empire, wherein Hernán Cortés, his army of Spanish conquistadors, and their native allies were driven out of the Mexica capital, Tenochtitlan.