emperor Montezuma II (1502-1520) succeeded his uncle Ahuitzotl as the leader of an empire that had reached its greatest extent, stretching from what is now northern Mexico to Honduras and Nicaragua. The Aztec empire was still expanding, and its society still evolving, when its progress was halted in 1519 by the appearance of Spanish adventurers. Montezuma was taken prisoner by Hernándo Cortés and died in custody. Montezuma's successors, Cuitláhuac and Cuauhtémoc, were unable to stave off the conquistadors and, with the Spanish sack of Tenochtitlán in 1521, the Aztec empire came to an end.