They are related to the Pima and Papago (Tohono O'odham) of Arizona and northern Sonora, speaking a similar but distinct language.

The population in 2010 was officially listed as 851, but this number swells to a few thousand on the holidays when people from small hamlets in the surrounding region congregate in Yepáchic.

In more recent decades, mestizos from the Mexican lowlands have migrated into the area, and now own most of the homes and nearly all the shops in the center of town.

This road was paved in 1990, resulting in regular bus service and a large amount of commercial trucking between Chihuahua and Hermosillo passing through the Pima region.

Estrada-Fernández studied the traditional indigenous Pima language, publishing an overview of their grammar, syntax and vocabulary.

He wrote that traditional rituals such as Semana Santa [Holy Week] play an important role in inter-ethnic relations.

[5][6] Pennington gathered information on use of medicinal plants by the people of Yepáchic[7] Laferrière continued the ethnobotanical work in the area.

He investigated the use of wild and cultivated plants in Yepachic and in the outlying hamlet of Nabogame, 18 km (11 mi) to the northwest.

[12][13][14] Most of the people in Yepáchic are Roman Catholics, practicing an antiquated form of the faith taught to them by missionaries centuries ago.

On Good Friday, men carry around the town a platform laden with adobe bricks, along a route that begins and ends at the church.