The Triple Alliance began with the assassination of Chimalpopoca, the Mexica ruler at that time. Trying to defeat Maxtla, who had assassinated Chimalpopca, Chimalpopca's successor, Itzcoatl formed an alliance with the exiled ruler of Texcoco, Nezahualcoyotl. This was the beginning of the Triple Alliance, which would come to rule the Aztec empire. Over the next century, Tenochitlan became the most powerful out of the 3 cities of Tenochitlan, Texcoco, and Tlacopan. The Aztecs became to most powerful civilization of the time. dominating the Gulf of Mexico to the Pacific. Over time, Tlacopan had nearly disappeared from the Triple Alliance, in which Tenochitlan (who held it`s power) and Texcoco ruled. The Aztecs reached their peak of power in the reign of Ahuizotl, in which the once triumphant empire had faded from history, destroyed by the Spanish.