Moctezuma I went down in oblivion, while his namesake, Moctezuma II, went down in infamy. The former is a terrible shame, the latter a vexing mystery.
Moctezuma I transformed the small Aztec city-state of Tenochtitlán into an empire. With his brilliant statesmanship, he created The Triple Alliance with Texcoco (ruled by his friend and ally, Nezahualcoyotl) and a lesser city-state, Tlacopan. Under his leadership, they conquered virtually all other tribes and states in central Mexico, shared the spoils, and grew incredibly wealthy.
Nezahualcoyotl designed and Moctezuma I built dikes on Lake Texcoco that separated brackish water from fresh; as well as twin aqueducts to bring that fresh water to their cities. They washed their streets and themselves daily (which caused them to see the conquering Spaniards, who eschewed bathing, as barbarians).
Moctezuma I thus established a “Pax Azteca,” an epoc of astounding prosperity and power for Tenochtitlán and its allies. Nonetheless, his achievements were far overshadowed by his successor’s failures.
Moctezuma II, who ruled a half century later, was no slouch himself. He expanded the empire he’d inherited, fighting bravely at the head of his armies and winning 43 battles.
But when Moctezuma II confronted Cortés, he became uncharacteristically indecisive. History has long accepted Cortés’ explanation, that Moctezuma II had mistakenly believed Cortés to be the reincarnation of the long-anticipated god, Quetzalcoatl. Thus, he foolishly welcomed Cortés into Tenochtitlán and even housed him in his palace; but Cortés repaid his hospitality by taking him hostage. Eventually, Moctezuma’s own people stoned him in frustration (although it may have been Cortés, equally frustrated, who administered the coup de grace).
Modern historians doubt this version, though, but maddeningly have proffered none of their own. Why, then, would a fierce warrior surrender obsequiously to a clearly much-weaker foe? Alas! This remains an enigma for the ages.