Beneath an Emerald Green Flag
The Story of Irish Soldiers in Mexico

By Michael G. Connaughton

Dennis Conahan, John Daly, John Sheehan, Thomas Cassidy, Patrick Casey. These names with a familiar Hibernian ring to them lay etched upon a rectangular stone tablet hung unassumingly on a building at the far end of the square. This simple memorial commemorated soldiers who had fought and died for a country attacked and invaded by her neighbour.

The memorial that I came across that bright early summer morning was not in West Cork or South Armagh nor was it on the site of an old battleground on the Western Front. It was in Plaza San Jacinto in San Angel, a suburb of Mexico City. Dedicated to the San Patricios or San Patrick’s Battalion, it honoured a group of mainly Irish-born American soldiers who changed sides and fought for Mexico in the US-Mexican War (1846-1847).

Their reasons for defection vary according to whom one consults. Those sympathetic to the San Patricios state that they drew parallels between US invasion of Mexico and the plight brought upon Ireland by her colonial master. They also point out that it was anti-Catholic bigotry within the WASP-dominated US officer corps that compelled them to fight alongside their fellow Catholics in Mexico. Those unsympathetic state that their motivations were purely financial claiming that the Mexicans merely offered them land and money. Other prejudiced opinions that would not look out of place amongst the pages of an old Punch magazine assert that alcohol was their primary incentive.

Their defection may still be a matter for conjecture, however what is for certain is that Galway-born John Riley, a US artillery lieutenant, led this band of Irish soldiers together with a smattering of German, Scottish and American Catholics across lines on the outbreak of hostilities in 1846. Their expert knowledge of artillery and infantry warfare proved invaluable to the Mexican army lead by General Santa Anna. They strode into numerous battles under an emerald green flag with Erin Go Bragh emblazoned across it and fought courageously in most of the war’s major engagements. Ultimately, however, their endeavours came to an end when, after ferocious close-quarter fighting, they were routed at the decisive Battle of Churubusco on 20 August 1847.

A horrendous fate awaited those who survived the battle and surrendered to US American forces. As deserters they were found guilty of treachery by a military court-martial. Forty-eight of the San Patricios were sentenced to death by hanging. The rest were branded with the letter ‘D’ for deserter and sentenced to severe floggings and long terms of imprisonment.

At daybreak on 13 September 1847 the condemned men were led to the gallows on a ridge overlooking the final battle of the war at Chapultepec Castle just outside Mexico City. Colonel William Harney, the US executioner, insisted that their hanging would only take place once he sighted the US American flag flying over the castle. The men waited agonisingly for hours in the baking heat with nooses around the necks providing a constant reminder, if they needed one, of their impending death. Francis O’Connor, one of the condemned men, had only recently had both legs amputated due to injuries sustained in battle. Finally at 9:30am their former comrades flew the Stars and Stripes signalling the final defeat of Mexican forces. Colonel Harney gave the order and the San Patricios entered Mexican folklore.

Hanging of the San Patricios following the Battle of Chapultepec
(Sam Chamberlain, c1867)

Almost 160 years after the event the story of the San Patricios still resonates in Mexican society. Each year in Plaza San Jacinto a commemoration in their honour is faithfully attended by dignitaries from the Mexican government and military, Irish embassy staff as well as members of the public. An honour guard of elite Mexican soldiers salutes them and both the Irish and Mexican national anthems are played. The current Mexican president Vicente Fox Quesada, himself of Irish descent, proclaimed in 2003 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”.

As I embarked on my trip home to England the taxi driver who brought me to Mexico City airport acknowledged the San Patricios when I happened to mention that I was Irish. “Ah your soldiers” he exclaimed in broken English as he veered erratically in and out of traffic on the busy airport road, they were very brave, they fought for my country you know?”. His sentiments are echoed by many people throughout Latin America. From the River Plate in Argentina to the Rio Grande on the Mexican-US border many Irishmen fought and gave their lives in the epic wars and independence struggles of the nineteenth century for nations far removed from their own. It is certain that they went on to provide inspiration to those who would finally achieve independence the following century in their homeland.

Dedicated to Brian McGinn, the man who fostered my interest in Irish-Latin American history, who sadly passed away on 20 July 2005.  

Contrasting Histories

The San Patricios is a controversial story. The late military historian Brian McGinn rightly pointed to the fact that "from the viewpoint of the U.S. military, the less said about such subjects, the better. Desertions reflect poorly on political leadership and military command; defections even more so. [...] In general, Irish-Americans have also been uncomfortable with the story of the San Patricios. They could argue, and convincingly, that the overwhelming majority of the 4,811 Irish-born soldiers who served in the U.S. army during the Mexican-American War did not desert. Even if all the San Patricios soldiers were Irish--and they were not--Irish-born deserters would represent less than four per cent of Irish soldiers" (The San Patricios: An Historical Perspective in "irishdiaspora.net").

In the website of the Descendants of Mexican War Veterans, the San Patricios battalion is depicted as "a group of mostly Irish deserters from the U.S. Army who joined the Mexican Army and fought against their former comrades during several battles of the U.S.-Mexican War. These turncoats were among the defenders of the convent of Churubusco [...]. In Mexico, the San Patricios are venerated as martyrs and heroes. Americans, on the other hand, generally see them as traitors who got what they deserved. To some, it seems unfair that the San Patricios have received so much attention while the thousands of Irish immigrants who served honorably in the U.S. Army have largely been ignored" (The U.S.-Mexican War, Frequently Asked Questions About the U.S.-Mexican War).


Copyright © Michael G. Connaughton
September 2005


The Society for Irish Latin American Studies, 2005

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