The calendrical systems devised and used by the pre-Columbian cultures of Mesoamerica, primarily a 260-day year, were used in religious observances and social rituals, such as divination.

Mesoamerica is a historical region and cultural area that begins in the southern part of North America and extends to the Pacific coast of Central America, thus comprising the lands of central and southern Mexico, all of Belize, Guatemala, El Salvador, and small parts of Honduras, Nicaragua and Costa Rica. As a cultural area, Mesoamerica is defined by a mosaic of cultural traits developed and shared by its indigenous cultures.