European colonists initially used the phrase to describe attacks by indigenous Americans which resulted in mass colonial casualties.

Killings described as "massacres" often had an element of indiscriminate targeting, barbarism, or genocidal intent.

"[4] It is difficult to determine the total number of people who died as a result of "Indian massacres".

His parameters for inclusion included the intentional and indiscriminate murder, torture, or mutilation of civilians, the wounded, and prisoners.

After the Fall of Tenochtitlan the remaining Aztec warriors and civilians fled the city as the Spanish allies, primarily the Tlaxcalans, continued to attack even after the surrender, slaughtering thousands of the remaining civilians and looting the city.