During the Mexican-American War of 1846-1848, the St. Patrick’s Battalion, (Battallon de San Patricio), was a group of several hundred immigrants, primarily Irish and German Catholics, who fought against the United States as a noteworthy arm of the Mexican army.

The “San Patricios” became a respected part of the Mexican Army during the war, but their bravery and military skills remain largely an unchronicled part of the history of the Southwest and Mexico.

Most of the battalion’s members were deserters from the U.S. Army who chose military service because other jobs were not available to them. When Irish immigrants arrived at northeastern ports in the United States, fleeing from the extremely dire economic conditions caused by the Irish Potato Famine, they endured mistreatment at the hands of their Anglo-Protestant officers and experienced prejudice in the U.S. Army.

The San Patricios were considered traitors at home, but became an integral fighting force for the Mexican army. The Mexican government offered incentives to foreigners who would enlist in its army; not only were the immigrants granted citizenship, but the Mexican army paid higher wages to these soldiers than had the U.S. Army, and also awarded them generous land grants. Some historians theorize that another motivating factor was the Catholic religion the Irish shared with their Mexican counterparts, as well as the similarity of the political situations in Ireland and Mexico.

Led by Captain John Riley of Clifden in County Galway, the corps referred to themselves as the St. Patrick’s Battalion. The soldiers fought against the U.S. forces in all of the war’s major campaigns, and, according to their Mexican comrades, “deserved the highest praise because they all fought with daring bravery.”

It was at the battle of Churubusco, the “Waterloo” for the Mexican Army, that the San Patricios suffered their most severe casualties, despite their exemplary military accomplishments.

In the end, Mexico was no match for the U.S. Army, and surrendered, thereby relinquishing control of the modern Southwest to the United States. Every San Patricio soldier who had deserted the U.S. Army was jailed and subsequently court-martialed. Others were set free, but more than half of the Irish were executed, paying the ultimate price for their crime.

In 1959, a commemorative plaque listing all the names of the San Patricios battalion, (including not only Irish, but Scottish and German immigrants also comprising the corps), who lost their lives in battle and execution, was dedicated in the Mexico City suburb of San Angel.

A special medallion immortalizing the San Patricios battalion was authorized by the Mexican government in 1983. At the celebratory Mass, school children placed floral wreaths at the plaque; the Mexico City Symphony orchestra played the national anthems of both Mexico and Ireland; and the “Irish Martyrs” were eulogized by Irish and Mexican officials in attendance.

In Ireland, Captain John Riley’s hometown of Clifden began their own annual observance in 1993.

St. Patrick is the patron saint in many towns in Mexico, and the triad of Melaque, Villa Obregon, and San Patricio celebrate St. Patrick’s Day with the Fiesta del Torros, a festival which features a rodeo, bullfights, folk dancing and fireworks.

A few words for St. Patrick’s Day in Spanish:

Clover – el trébol
Emerald Isle – Irlanda
Green – verde
Ireland – Irlanda
Leprechaun – duende or gnono
Lucky – afortunado, suertudo
Pot of gold – La olla or perol de oro
Rainbow – el arco iris
St. Paddy’s Day – el día de San Patricio
shamrock – el trébol
Wish – el deseo. Pedir un deseo is to make a wish