The battle ended with both sides negotiating a two-month armistice and the Mexican forces being allowed to make an orderly evacuation in return for the surrender of the city.

Following the Battle of Resaca de la Palma, Taylor crossed the Rio Grande on 18 May, while in early June, Mariano Arista turned over command of what remained of his army, 2,638 men, to Francisco Mejia, who led them to Monterrey.

A. Nieto)) and an artillery unit, the largely Irish-American volunteers called San Patricios (or the Saint Patrick's Battalion), in their first major engagement against U.S. forces.

[1]: 92  Taylor ordered the army to camp at Bosque de San Domingo while engineers under the command of Major Joseph K. Mansfield reconnoitered.

"San Patricio" Battery); "the Tannery," La Teneria, (2d Ligero under Col. José M. Carrasco and part of the Querétaro Battalion, and 2 guns & 1 mountain howitzer – Lt (?)

Ignacio Joaquin del Arenal); La Purísima bridge and tete-de-pont (Activos of Aguascalientes under Col. Jose Ferro and the Querétaro under Comdte.

[1]: 93  Worth started at 2 pm on 20 September with Col. John Coffee Hays's Texas Mounted Riflemen Regiment screening the advance, but camped for the night three miles from the Saltillo road.

[1]: 94 In the meantime, Taylor launched a diversion against eastern Monterrey with Col. John Garland's 1st and 3d Infantry plus Lt. Col. William H. Watson's Maryland and District of Columbia Battalion, which quickly grew into an assault.

Electus Backus's company of the 1st Infantry had taken the tannery and by noon, with Col. William B. Campbell's 1st Tennessee and Mississippi Rifles, had taken Fort de La Teneria.

[1]: 97, 99 During the exchange of fire, a young Mexican woman named María Josefa Zozaya wandered into the crossfire to tend to the wounds of injured soldiers of both armies.

Taylor was lambasted by some in the federal government, where President James K. Polk insisted that the U.S. Army had no authority to negotiate truces, only to "kill the enemy."

Among the most memorable massacres is the one reported by the Houston Telegraph and Register on January 4, 1847 when Texas volunteers blamed the Mexicans for the death of several of their companions in Monterrey.

In response to the occupation several local guerrilla groups emerged such as those led by Antonio Canales Rosillo and José Urrea, the latter widely repudiated by the Texans because of his leadership participation in the campaigns of the Texas War ten years earlier.