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When the Irish fought to Save Mexico: The St. Patrick's Battalion

Updated: Apr 13, 2021

Ireland is country full of outstanding people and astonishing natural beauty, both represented by the warmth and good humor of the Irish and the green of its pastures. No wonder they call her the Emerald Island! From its unique music to its unmistakable spirits and beverages, Ireland has exported its culture to the four corners of the globe bringing joy to millions, this made specially true each year the 17th March: St. Patrick's Day.

St. Patrick's Day in countries like Canada, Australia, the US, New Zealand, Brazil, and Argentina celebrates the Irish culture and heritage brought by the Irish diaspora (Irish people and their descendants who live outside of Ireland). But in Mexico it takes a different more commemorative meaning.

This day we remember the brave soldiers of the St. Patrick's Battalion, commander John O'Riley and all those who defected from the US Army to fight with the Mexicans against a common enemy: oppression.

A bit of History: The Mexican-American War

Soldiers don't defect out of nowhere, let's start from the beginning. In 1846 the Mexican-American war started following the annexation of Texas to the US in 1845, this because the Mexican government didn't recognize Texa's independence. There were already disputes between both nations as American President James K. Polk was elected on a basis of expanding US territory by any means necessary and Mexico had a lot of internal political conflict. Mexico was tricked into moving troops closer and closer to American troops guarding the Nueces River until, eventually, it sparked conflict. This gave Polk the excuse he needed to convince Congress the Mexicans had started the war.

At the same time Ireland was suffering from the Great Famine, this caused many Irish to escape to America in search for a better life. Young men would be enlisted at their arrival into the US Army with the promises of a salary and land, promises that weren't kept. It isn't a secret that the Irish were oppressed and abused for years to come in America, as other immigrants also were, saying to have sparked numerous reasons for their defection.

Among these reasons we have:

  1. Mistreatment of immigrant soldiers: Nativist soldiers and senior officers would culturally alienate foreign conscripts. They saw them as nothing more than canon fodder.

  2. Brutal military discipline: as most of them were conscripted on arrival the dislike for service in the military wasn't a surprise. This pushed officers to create harsh conditions to achieve discipline.

  3. Being forced to attend Protestant church services: the Irish were unable to practice their Catholic religion freely.

  4. Higher wages and land grants offered by Mexico: starting at 320 acres, the Mexican government was not shy in offering better conditions than the US did. Mexico printed propaganda to get immigrant soldiers to defect by offering a living wage, freedom to practice Catholicism and Mexican citizenship, the last one being the most enticing. Historically around 9,000 troops defected to Mexico, not only Irish also Black slaves, Germans, Canadians, English, French, Italians, Poles, Scots, Spaniards, and Swiss.

  5. Viewing the U.S. invasion of Mexico as unjust: the Irish were not only escaping the famine but also the British crown, most of them saw the war with Mexico as nothing more than a land grab by an oppressive government. Exactly what the British did to their land, these similarities between the Mexico and Ireland are what most historians agree to be the strongest reason for the defection.

Commander John O'Riley convinced around 200 Irishmen to defect to the Mexican army where they were transformed from an artillery battalion to two infantry companies, O'Riley was given command of both. The Mexicans started calling all soldier in these companies los San Patricios.

The Tragic End

The San Patricios fought bravely in many battles including one considered to be the bloodiest and most difficult, The Battle of Churubusco, were 72 San Patricios were captured and trialed as traitors to the US Army.

Two court-martials were held, at neither were the men represented by lawyers, most of the San Patricios offered no defense. It's said that some wealthy Mexicans came to the San Patricios' defence and visited them in prison. The San Patricios were sentenced to death by hanging, a form of execution that was in total violation of the Articles of War, which stipulated that the penalty for desertion/defection was death by firing squad, regardless of the circumstances. Hanging was reserved for spies and war criminals, neither of which describe the San Patricios. From the 9,000 men that defected to the Mexican army it was only the San Patricios who suffered this dishonor.

These soldiers received 50 lashes on their bare backs, they were branded with the letter 'D' for deserter, and to wore iron yokes around their necks until the end of the war. 50 San Patricios were executed, this was the largest mass execution by the US Army after the hanging of 38 Sioux at the conclusion of the Dakota War of 1862. From this 50 men 30 San Patricios were executed at Chapultepec in full view of the two armies while they were still engaged in battle. This order was carried out by Col. William Harney who was taunted and jeered by the condemned men. Harney ordered Francis O'Connor hanged, a man who had both legs amputated the earlier day. The army surgeon informed the colonel that the absent soldier had lost both his legs, Harney replied: "Bring the damned son of a bitch out! My order was to hang 30 and by God I'll do it!"

In a final act of defiance, the San Patricios cheered the Mexican flag, as one man yelled; "Hands tied, feet tied, their voices still free".

Harney refused to cut the bodies down, "I was ordered to have them hanged, and have no orders to unhang them", he was promoted to brigadier general soon after. The Mexican government described the hangings as "a cruel death or horrible torments, improper in a civilized age, and ironic for a people who aspire to the title of illustrious and humane". In this I agree with the Mexican government.

The Unification of Ireland and Mexico

The San Patricios who survived the war got everything they were promised and went on to make lives for themselves in Mexico. Since then, Mexico raises an Irish flag every 17th March to honor those brave soldiers who in the face of oppression and injustice decided to fight for what they believe. In 1997 the President of Mexico said these words; "Members of the St. Patrick's Battalion were executed for following their consciences. They were martyred for adhering to the highest ideals ... we honor their memory. In the name of the people of Mexico, I salute today the people of Ireland and express my eternal gratitude". I would like to salute you and your land too.

It's easy to say that the Irish chose to fight for Mexico because they came from a Catholic country too, but I believe this is an insult to the fighting spirit of the Irish. I would even go further and say Irish and Mexicans are cut from the same cloth, we share an infinite love for our people and an unwavering hate for foreign oppression. Our countries have been united since, I hope our friendship lasts forever. Erin Go Bragh!

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