In September 1835, he was sent by President-General Antonio López de Santa Anna to investigate the refusal of Texians to pay duties during the Anahuac Disturbances.

General Cos dispersed the legislature of Coahuila y Tejas, then in session at Monclova, landed 300 men at Matagorda Bay, established a headquarters in San Antonio, and declared his intention of ending Anglo-American resistance in Texas.

San Antonio had always governed its own affairs and its citizens, increasingly ethnic Anglo-Americans with closer ties to the emerging United States, resented Cos being given power over them.

[5] Cos arrived in Texas by sea at the port of Copano on September 20, 1835, with 500 soldiers[6] and proceeded to the town of Goliad on October 1, where he ordered the arrest of rebel leaders and garrisoned his men inside the nearby Presidio La Bahía.

After a 56-day siege of the town and the Alamo Mission, on December 9, Cos surrendered San Antonio de Béxar and its weapons to the Texians, then proceeded to retreat back across the Rio Grande.

[9][10] That afternoon Texian forces led by General Sam Houston decisively defeated Santa Anna's army in a battle which lasted only eighteen minutes.

[2] Among the depictions of Martín Perfecto de Cos on film is that of the Mexico City-born actor Rodolfo Hoyos Jr., in the 1956 picture The First Texan, about the rise of Sam Houston in Texas.