War was a fact of life in Aztec society. The empire was built and maintained on warfare or the threat of it. During lulls when there was no major fighting, the Triple Alliance conducted "flowery" wars against a common enemy just to train new warriors, keep veterans in top fighting form, and maintain a steady flow of prisoners for sacrifice.

The purpose of war for the Aztecs was to gain tribute from conquered peoples rather than to colonize or govern their territories. The type of warfare the Aztecs conducted was geared to that end—to force a surrender of an enemy by combat or negotiation, to draw up a contract of tribute expected from the vanquished, and to severely punish those groups who failed to live up to the demands or who showed signs of rebellion. The punishment served as a deterrent to other groups who might...