<P> The Spanish conquest of the Aztec Empire, or the Spanish--Aztec War (1519--21), was the conquest of the Aztec Empire by the Spanish Empire within the context of the Spanish colonization of the Americas . It was one of the most significant and complex events in world history . There are multiple 16th - century narratives of the events by Spanish conquerors, their indigenous allies and the defeated Aztecs . It was not solely a contest between a small contingent of Spaniards defeating the Aztec Empire but rather the creation of a coalition of Spanish invaders with tributaries to the Aztecs, and most especially the Aztecs' indigenous enemies and rivals . They combined forces to defeat the Mexica of Tenochtitlan over a two - year period . For the Spanish, the expedition to Mexico was part of a project of Spanish colonization of the New World after twenty - five years of permanent Spanish settlement and further exploration in the Caribbean . </P> <P> The Spanish made landfall in Mexico in 1517 . A Spanish settler in Cuba, Hernán Cortés, led an expedition (entrada) to Mexico, landing in February 1519, following an earlier expedition led by Juan de Grijalva to Yucatán in 1517 . Two years later Cortés and his retinue set sail, thus beginning the expedition of exploration and conquest . The Spanish campaign against the Aztec Empire had its final victory on August 13, 1521, when a coalition army of Spanish forces and native Tlaxcalan warriors led by Cortés and Xicotencatl the Younger captured the emperor Cuauhtemoc and Tenochtitlan, the capital of the Aztec Empire . The fall of Tenochtitlan marks the beginning of Spanish rule in central Mexico, and they established their capital of Mexico City on the ruins of Tenochtitlan . </P> <P> Cortés made alliances with tributaries city - states (altepetl) of the Aztec Empire as well as their political rivals, particularly the Tlaxcalteca and Texcocans, a former partner in the Aztec Triple Alliance . Other city - states also joined, including Huexotzinco and polities bordering Lake Texcoco, the inland lake system of the Valley of Mexico . Particularly important to the Spanish success was a multilingual (Nahuatl, a Maya dialect, and Spanish) indigenous slave woman, known to the Spanish conquistadors as Doña Marina, and generally as La Malinche . After eight months of battles and negotiations, which overcame the diplomatic resistance of the Aztec Emperor Moctezuma II to his visit, Cortés arrived in Tenochtitlan on November 8, 1519, where he took up residence with fellow Spaniards and their indigenous allies . When news reached Cortés of the death of several of his men during the Aztec attack on the Totonacs in Veracruz, he took Moctezuma captive, along with Cuitláhuac, his kinsman . Capturing the cacique or indigenous ruler was standard operating procedure for Spaniards in their expansion in the Caribbean, so capturing Moctezuma had considerable precedent, which might well have included those in Spain during the Christian reconquest of territory held by Muslims . </P> <P> When Cortés left Tenochtitlan to return to the coast and deal with the expedition of Pánfilo de Narváez, sent to rein in Cortés's expedition that had exceeded its specified limites, Cortés's right - hand man Pedro de Alvarado was left in charge . Alvarado allowed a significant Aztec feast to be celebrated in Tenochtitlan and on the pattern of the earlier massacre in Cholula, closed off the square and massacred the celebrating Aztec noblemen . The official biography of Cortés by Francisco López de Gómara contains a description of the massacre . The Alvarado massacre at the Main Temple of Tenochtitlan precipitated rebellion by the population of the city . Moctezuma was killed, although the sources do not agree on who murdered him . According to one account, when Moctezuma, now seen by the population as a mere puppet of the invading Spaniards, attempted to calm the outraged populace, he was killed by a projectile . According to an indigenous account, the Spanish killed Moctezuma . Cortés had returned to Tenochtitlan and his men fled the capital city during the Noche Triste in June 1520 . The Spanish, Tlaxcalans and reinforcements returned a year later on August 13, 1521 to a civilization that had been weakened by famine and smallpox . This made it easier to conquer the remaining Aztecs . </P>

Who was the leader of the aztecs when the spanish soldiers invaded their land