Soldados de cuera manned presidios on the Spanish frontier. Most of them were born in the frontier provinces of New Spain and were adapted to harsh living conditions. They came from a variety of backgrounds. Many were mestizos, or mixed European and Indian. Some were mulato. Others were criollos, or Españoles born in America, and some were peninsulares or gachupines or Spanish from the Iberian Peninsula.

The soldado de cuera was named for his leather cuera armor. The cuera was a heavy leather, knee-length, sleeveless coat. A soldado carried a shield or an adarga and had six horses and one mule at his disposal.