Coahuila y Tejas (Coahuila and Texas) is one of the constituent states of the newly established United Mexican States under its 1824 Constitution.

It has two capitals: first Saltillo, and then Monclova.

For administrative purposes, the state is divided into three districts: Béxar, comprising the area covered by Texas, Monclova, comprising northern Coahuila, and Río Grande Saltillo, comprising southern Coahuila.The state remains in existence until the adoption of the 1835 "Constitutional Bases", whereby the federal republic is converted into a unitary one, and the nation's states, (estados), are turned into departments (departamentos).

The State of Coahuila y Texas was split in two and became the Department of Coahuila and the Department of Texas.

The latter eventually secedes and becomes the independent Republic of Texas, which is today the state of Texas within the United States of America.Both Coahuila and Texas secede from Mexico because of Santa Anna's attempts to centralize the government, with Texas forming the Republic of Texas and Coahuila joining with Nuevo León and Tamaulipas to form the short-lived Republic of the Rio Grande.