Following the secession of Texas in February 1861 and its joining the Confederacy, a battalion of the
2nd Texas Mounted Rifles under Lieutenant Colonel
John R. Baylor was sent to occupy the series of forts along the western Texas frontier which had been abandoned by the Union Army. Baylor's orders from the Department of Texas commander, Colonel
Earl Van Dorn, allowed him to advance into New Mexico in order to attack the Union forts along the
Rio Grande if he thought the situation called for such measures. Convinced that the Union force at
Fort Fillmore would soon attack, Baylor decided to take the initiative and launch an attack of his own. Leaving during the night of July 23, Baylor arrived at Fort Fillmore the next night, preparing to launch a surprise attack the next morning. However, a Confederate deserter informed the fort's commander, Major
Isaac Lynde, of the plans. The next day, Baylor led his battalion across the Rio Grande into
Mesilla, which sat at the crossroads of the two most traveled trails in the Southwest, the north–south
El Camino Real de Tierra Adentro ("the Royal Road of the Interior Land") and the east-west Butterfield overland mail route. Baylor and his men were greeted with the cheers of the townspeople, who favored the Confederacy. A company of Arizona Confederates joined Baylor here, and were convinced to muster into the Confederate Army. On July 25, leaving a small force behind to guard the fort, Lynde led 380 Regulars to the village to drive out Baylor. ==Battle==