Montezuma II was the Aztec Emperor in the early 16th century, when the Spanish conqueror Hernando Cortez took over the land nowadays known as Mexico.

This conquest, or, massacre as you see fit, is detailed in the second letter of Cortez to the Emperor of Spain, which survives and is published to this day. The first letter had disappeared, and there are other 3. In this second letter, Cortez explains to Carlos V how he did piously allied himself with tribes who were oppressed by the Aztec, and how he lied to both his native allies and Aztecs alike, to get to Montezuma and wipe him and the Aztec Empire out of existence.

The information that survives on Montezuma himself is thus contained in this letter and may be summarized. In his first encounter with Cortez he brought with him an escort of 200 men just for the ritual of meeting him, next to the city of Tenochtitlán. The wealth described by Cortez is impressive - if you are talking about gold.

    Montezuma would change clothes four times a day, and those he took off, he would never use again.

    Montezuma's meals would follow a ritual,with a long line of young people bringing all kinds of food - birds, fish, fruit and vegetables that would fill a room.

    There were so many and so different the ceremonies this lord had to his service that it would be necessary more space than what I have to write about him.

from Cortez's Second letter

Montezuma died prisoner of Cortez before the end of October 1520, according to Cortez, hit by a stone from his own people. Prior to that he would have sworn obedience do the Emperor of Spain, thus bringing upon him the enmity of his peers, who were attacking the Spanish conquerors.