The Aztec Empire sacrificed hundreds of thousands in their religious rites prior to the defeat of the empire by the Spanish in 1521 and the outlawing of the practice of human sacrifice.
Pictured below is an example of the kind of obsidian blade the Aztecs would use for a variety of purposes, including sacrifices.
Obsidian is a volcanic glass that can be fractured down to a single atom. It has been argued that an obsidian cutting edge can be five hundred times sharper than the sharpest steel blade.
Ten years later Our Lady of Guadalupe would accelerate the conversion of the peoples of the Aztec Empire by teaching that only the sacrifice of Jesus Christ on the cross would be acceptable to God.