As I learn more about the Aztecs, and their advancements in civilisation and culture, I struggle to believe the arguably commonly-held belief that much of the foundation of the culture is based on violence.

It seems bizarre that the Aztecs would create cities so sophisticated and elaborate such as Tenochtitlan, only to then pursue comparatively barbaric practices within their advanced civilisation.

Is there any evidence that justifies the belief that Aztec religion revolved around human sacrifice, or is this belief just remnants of Spanish propaganda that have been warped and exaggerated over time, and are now believed to be true?