Santa Anna retreats five miles (eight kilometers)…

Santa Anna retreats five miles (eight kilometers) back to a fortified convent at Churubusco, where Scott’s men, approaching under heavy fire, force the convent’s surrender on August 20.

Santa Anna escapes with much of his command, suffering the loss of four thousand killed or wounded and over twenty-five hundred captured; American casualties are just over one thousand.

The most famous group of deserters from the U. S. Army is the Saint Patrick's Battalion or (San Patricios), composed primarily of several hundred immigrant soldiers, the majority Catholic Irish and German immigrants, who have deserted the U.S. Army because of ill-treatment or sympathetic leanings to fellow Mexican Catholics and joined the Mexican army.

The battalion also include Canadians, English, French, Italians, Poles, Scots, Spaniards, Swiss, and Mexican people, many of whom are members of the Catholic Church.

Most of the battalion are killed in the Battle of Churubusco; about one hundred are captured by the U.S. and roughly half of the San Patricios will be tried and were hanged as deserters.

The leader, Jon Riley, is merely branded since he had deserted before the war started.