Things That Matter

In Mexico, St. Patrick’s Day Commemorates the Irish-Americans Who Defended Mexico During the Mexican-American War

When you think of Saint Patrick’s Day in the U.S., you probably think of Guinness beer, corned beef and cabbage. But in Mexico, St. Patrick’s Day symbolizes something very different.

In Mexico, St. Patrick’s Day is a day to commemorate the San Patricios battalion in the Mexican-American War — a Mexican army regiment made up of primarily Irish-Catholic immigrants who deserted the U.S. Army to fight for Mexico.

As a refresher, the Mexican-American war was a war between the United States and Mexico that was fought between 1846 and 1848. The war began as part of the U.S.’s philosophy of “manifest destiny” — the belief that the U.S. was destined by God to expand across North America. The nation’s goal was to annex a chunk of Mexico’s land — what now makes up eight states in the U.S., including Texas.

The flag of the San Patricios Battalion (Public Domain)

The San Patricios Battalion was made up of over 200 men, led by Irish-American commander John Riley. The men were involved in six known battles, including the important Battle of Buena Vista. They faced their final defeat in the battle of Churubusco.

There are a myriad of reasons that so many Irishmen decided to switch sides and fight for Mexico so long ago. In general, historians agree the primary reasons were frustration over the prejudice they experienced as Irish immigrants in the U.S. Army, anger over being forced to attend Protestant services and a general disagreement over how the U.S. was invading and taking over Mexican territory. 

Not only that, but the Mexican government conducted a successful propaganda campaign targeted at Irish-Catholic soldiers. They successfully appealed to the soldiers’ morality, religion and desire for economic freedom. 

In one pamphlet written by Mexican General Ampudía, he urged U.S. soldiers not to “contribute to defend robbery and usurpation [of Mexican land] which, be assured, the civilized nations of Europe look upon with the utmost indignation.” 

Another Mexican commander offered any U.S. soldier who deserted “320 acres of good land.” According to contemporary sources, Catholic Priests in Mexico were also instrumental in recruiting U.S. soldiers to fight for Mexico. 

After the San Patricios battalion was defeated at Churubusco, the deserters were punished harshly by the U.S. military, as they were considered traitors. Approximately 50 soldiers from the San Patricios battalion were hanged, while some were whipped and branded with the letter “D” to label them deserters and sentence them to hard labor. 

Commemoration plaque to the Battalion San Patricio (Creative Commons)

Today, both Mexico and Ireland honor the men who risked it all to fight for the side they believed in. In 2003, then-president of Mexico Vicente Fox honored the San Patricios Battalion in a speech, saying that “the affinities between Ireland and Mexico go back to the first years of our nation, when our country fought to preserve its national sovereignty… Then, a brave group of Irish soldiers… in a heroic gesture, decided to fight against the foreign ground invasion.” 

In 1997, Mexico and Ireland jointly released a postage stamp to commemorate the bravery of the soldiers of the San Patricios Battalion on the 150th anniversary of the soldiers’ death.

And every year on March 17, Mexico uses the holiday of St. Patrick’s Day to honor the men who bravely fought for their country.

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