Many of the disgruntled Aztec subjects flock to Cortés’ side as he marches inland with his army of about four hundred Spaniards and six thousand native Cemoalan and Tlaxcalan auxiliaries.

Cortés’ invasion force according to the Aztec calendar had landed in Mexico on the day One Reed, the calendar day of the hero-god Quetzalcoatl's birth.

Quetzalcoatl, a title taken by several historical rulers and heroes since the driving out of King Topiltzin Quetzalcoatl from the city of Tula in the twelfth century, has become central to mythological stories about the deification of the god-man and his promise to return and claim his earthly kingdom.

This still-current prophecy has apparently caused Moctezuma to regard Cortés as a deity, perhaps Quetzalcoatl himself.

The Spaniards reach the Aztec’s island capital of Tenochtitlan in November 1519, and, after a study of omens and prophecies persuades Motecuhzoma that the invaders are gods, he concludes that he is doomed.

He chooses not to fight the Europeans but to deter them by trickery, magic, and gift offerings.

Failing in this, Moctezuma permits Cortés and his men to enter Tenochtitlán unopposed by the formidable imperial armies.

Cortés and his forces enter the island capital of the Mexica-Aztecs, on November 8, 1519.

Of all the cities in Europe, only Constantinople is larger than Tenochtitlan.

The most common estimates put the population at around sixty thousand to over three hundred thousand people.

The largest city in Spain, for example, is Seville, which has a population of only thirty thousand.

According to the Aztec chronicles recorded by Sahagún, the Aztec ruler Moctezuma II welcomes Hernán Cortés, El Caudillo, with great pomp, on the Great Causeway.

According to Sahagún's manuscript, Moctezuma personally dressed Cortes and his commanders with flowers.

In turn, Cortés attempted to embrace the Emperor but was restrained by a courtier.

This contradiction between "the arrogant emperor' and the "humble servant of Quetzalcoatl" has been problematic for historians to explain and has led to much speculation.

However, all the proscriptions and prohibitions regarding Moctezuma and his court had been established by Moctezuma and were not part of traditional Aztec customs.

Those prohibitions had already caused friction between Moctezuma and the pillis (noble classes).

There is even an Aztec legend in which Huemac, the legendary last lord of Tollan Xicotitlan, instructed Moctezuma to live humbly and eat only the food of the poor, to divert a future catastrophe.

Thus, it seems out of character for Moctezuma to violate rules that he himself had promulgated.

Yet, as supreme ruler, he had the power to break his own rules.

Moctezuma has the royal palace of Axayácatl, Moctezuma's father, prepared for Cortes.

Later the same day that the Spanish expedition and their allies enter Tenochtitlan, Moctezuma come to visit Cortés and his men.

What happened in this second meeting remains controversial.

According to several Spanish versions, some written years or decades later, Moctezuma first repeated his earlier, flowery welcome to Cortés on the Great Causeway, but then went on to explain his view of what the Spanish expedition represented in terms of Aztec tradition and lore, including the idea that Cortés and his men (pale, bearded men from the east) were the return of characters from Aztec legend.

At the end of this explanation, the Emperor pledges his fealty to the King of Spain and accepts Cortés as the King's representative.

According to Diaz, Moctezuma said to Cortes, "As for your great king, I am in his debt and will give him of what I possess."

While in the Axayacatl palace, the Spaniards discover the secret room where Moctezuma keeps the treasure he had inherited from his father.

The treasure consists of a "quantity of golden objects - jewels and plates and ingots".

Diaz noted, "The sight of all that wealth dumbfounded me."

Cortés later asks Moctezuma to allow him to erect a cross and an image of Virgin Mary next to the two large idols of Huichilobos and Tezcatlipoca, after climbing the one hundred and fourteen steps to the top of the main temple pyramid.

Moctezuma and his priests are furious at the suggestion, with Moctezuma claiming his idols, "give us health and rain and crops and weather, and all the victories we desire.”

The Mexica now kill seven Spanish soldiers Cortes had left on the coast, including Cortes' Villa Rica Constable Juan de Escalante, and many Totonacs.

Cortés, along with five of his captains and Dona Marina and Aguilar, persuades Moctezuma to "come quietly with us to our quarters, and make no protest...if you cry out, or raise any commotion, you will immediately be killed."

Moctezuma is later implicated by Qualpopoca and his captains, who had killed the Spanish soldiers.

Though these captains of Moctezuma are sentenced to be "burned to death", Moctezuma continues to remain a prisoner, fearing a "rebellion in his city" or that the Spanish may "try to set up another prince in his place."

This, despite Moctezuma's chieftains, nephews and relations suggesting they should attack the Spanish.

Moctezuma as of November 14, 1519, is Cortes' prisoner as insurance against any further resistance.

Moctezuma lives with Cortés in the palace of Axayácatl and continues to act as Emperor, subject to Cortés' overall control.

Cacamatzin, king of Texcoco, the second most important city of the Aztec Empire, is a son of the previous king Nezahualpilli by one of his mistresses.

Traditionally, the Texcocan kings are elected by the nobility from the most able of the royal family.

Cacamatzin's election to the throne in 1515 is said to have been made under considerable pressure from Moctezuma II, lord of Tenochtitlán.

Moctezuma II wishes to lessen Texcoco's power in favor of greater centralization in Tenochtitlán.

Moctezuma II, under orders from Cortes, had Cacamatzin arrested "in his own palace while discussing war-preparations".

The Caciques of Coyoacan, Iztapalapa, and Tacuba are also arrested.

Moctezuma and his caciques are forced after the treason of Cacamatzin  to take a more formal oath of allegiance to the King of Spain, though Moctezuma "could not restrain his tears".

Moctezuma told his Caciques that "their ancestral tradition, set down in their books of records, that men would come from the direction of the sunrise to rule these lands" and that "He believed...we were these men."

Cortés sends expeditions to investigate the Aztec sources of gold in the provinces of Zacatula, Tuxtepec, and the land of the Chinantecs.

Moctezuma is now made to pay a tribute to the Spanish king, which includes his father's treasure.

These the Spaniards melt down to form gold bars stamped with an iron die.

Finally, Moctezuma lets the Spaniards build an altar on their temple, next to the Aztec idols.

The Aztec gods tell the Mexican papas, or priests, they will not stay unless the Spaniards are killed and driven back across the sea.

Moctezuma warna Cortes to leave at once, as their lives are at risk.

Many of the nobility rally around Cuitláhuac, the brother of Moctezuma and his heir-apparent; however, most of them can take no overt action against the Spanish unless the order is given by the Emperor.

Moctezuma informs Cortés that a much larger party of Spaniards consisting of nineteen ships and fourteen hundred soldiers under the command of Pánfilo de Narváez had arrived.

Narváez had been sent by Governor Velázquez from Cuba to kill or capture Cortés.

Leaving his two hundred "least reliable soldiers" under the command of Pedro de Alvarado to guard Moctezuma in Tenochtitlan, Cortés sets out against Narváez, who has advanced onto Cempoala.

Alvarado meanwhile commits the massacre in the Great Temple, triggering a local rebellion.

Cortes now makes a rapid return to Tenochtitlan, to relieve the besieged Alvarado and his men.

Cortés, whose forces are numerically inferior, surprises his antagonist with a night attack, during which his men wound Narváez in the eye and take him prisoner.

He persuades the rest of Narváez's men to join him.

After Cortés permits the defeated soldiers to settle in the country, they "passed with more or less willingness to Cortes' side."

Cortes gains their support when he "promised to make them rich and give them commands.”

Among the group of Spanish that had arrived in Mexico from Hispaniola is one or more who is infected with the smallpox that had already been ravaging that island for two years.

In this contact between the two Spanish groups, one of Cortés's men contracts the disease.

When Cortés returns to Tenochtitlan, he brings the disease with him.