The Zacatecan municipalities it borders are Melchor Ocampo to the north, General Francisco R. Murguía to the west, Villa de Cos to the south and Concepción del Oro to the east.

Mazapil also borders the municipalities of Catorce, Santo Domingo and Vanegas, to the east, all part of San Luis Potosí; San Juan de Guadalupe in the state of Durango to the west; and Saltillo and Viesca to the north, both in Coahuila.

In 1562, Pedro de Ahumada y Samano reported finding the valley inhabited by 6000 native warriors armed with bows and arrows.

[11] Mazapil was one of Zacatecas's eleven original subdivisions (then known as partidos) when the state's constitution was enacted in 1825.

[9] Mazapil's municipal government comprises a president, secretary, councillor (Spanish: síndico), and six trustees (regidores).

[2] In the 2010 Mexican Census, the municipality of Mazapil recorded a population of 17,813 inhabitants living in 4275 households.