The Saint Patrick's Battalion (), later reorganized as the Foreign Legion of Patricios, was a Mexican Army unit which fought against the United States in the Mexican–American War. Consisting of several hundred mostly Irish and other Catholic European expatriates and immigrants, including numerous men who had deserted or defected from the United States Army, the battalion was formed and led by Irishman John Riley. It served as an artillery unit for much of the war, and despite later being formally designated as an infantry unit of two companies, the battalion continued to operate artillery pieces throughout the conflict. The participated in many of the bloodiest battles during the American invasion of Mexico, with Ulysses S. Grant remarking that "Churubusco proved to be about the severest battle fought in the valley of Mexico".
Composed primarily of Irish immigrants, the battalion also included German, Canadian, English, French, Italian, Polish, Scottish, Spanish, Swiss and Mexican soldiers, most of whom were Catholic. Several native-born Americans were in the ranks, including fugitive slaves from the Southern United States. Only a few members of the battalion were U.S. citizens. The Mexican government printed propaganda in different languages to entice immigrants serving in the United States Army to switch sides and offered incentives to foreigners who would enlist in its army, including being granted citizenship, being paid higher wages and generous land grants. U.S. Army regiments which had members defect included the 1st Artillery, the 2nd Artillery, the 3rd Artillery, the 4th Artillery, the 2nd Dragoons, the 2nd Infantry, the 3rd Infantry, the 4th Infantry, the 5th Infantry, the 6th Infantry, the 7th Infantry and the 8th Infantry. The are honored by Mexican and Irish people.
Historical perspective
For those Mexicans who had fought in the Mexican–American War and for generations to come after, the were heroes who came to their aid in an hour of need. For Americans, the were traitors, fighting in an unjust attempt by Mexico to reconquer Texas. Successive Mexican presidents have praised the ; Vicente Fox Quesada stated 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", and Mexican president Ernesto Zedillo stated "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".
Motivations The great majority of those men who formed Saint Patrick's Battalion were recent immigrants who had arrived at northeastern U.S. ports. They were part of the Irish diaspora then escaping the Great Irish Famine and extremely poor economic conditions in Ireland, which was at the time part of the United Kingdom of Great Britain and Ireland. The U.S. Army often recruited the Irish and other immigrants into military service shortly or sometimes immediately after arrival in America in coffin ships with promises of salaries and land after the war.
Numerous theories have been proposed as to their motives for desertion, including cultural alienation, mistreatment of immigrant soldiers by nativist soldiers and senior officers, brutal military discipline and dislike of service in the U.S. military, being forced to attend Protestant church services and being unable to practice their Catholic religion freely as well as religious ideological convictions, the incentive of higher wages and land grants starting at offered by Mexico, and viewing the U.S. invasion of Mexico as unjust.
It is believed primary motivations were shared religion with the Mexicans and sympathy for the Mexican cause based on similarities between the situations in Mexico and Ireland. This hypothesis is based on evidence of the number of Irish Catholics in the battalion, the letters of John Riley, and the field entries of senior officers. Irish immigrants had been faced with animosity both as a result of their Catholic faith and ethnicity. Catholic immigrants were regularly met with discrimination from their Protestant peers, sentiments which sometimes boiled over into events such as the Philadelphia nativist riots against Irish Catholic immigrants. Catholic churches had been similarly defaced by the American military in Mexico during the war. Additionally, both the Mexicans and the Irish were subjected to racism and xenophobia based on 'scientific racism' and treated as inferior to American nativists.
Another hypothesis is that the members of the Saint Patrick's Battalion had been unhappy with their treatment in the U.S. Army; this was the conviction of George Ballentine, an Englishman who served in the American army. Ballentine stated that while "there was a portion of truth" in the view—commonly assigned by officers—that the deserters joined the Mexican army due to their Catholicism; he said, "I have good reason to believe, in fact in some cases I know, that harsh and unjust treatment by their officers operated far more strongly than any other consideration to produce the deplorable result [desertion]," and described how he found the punishments used for "trivial offensives" to be "revolting and disgusting". Another theory some historians hold is that the soldiers were attracted by the incentives offered by the Mexican government: safe passage throughout Mexico for deserters, generous land grants, and the offer of potential military commissions. For poor people coming from famine conditions, economics was often an important incentive.
Mexican author José Raúl Conseco noted that many Irish lived in northern Texas, and were forced to move south due to regional insecurity. Mainly Irish settlers from San Patricio, Texas, had previously sided with Mexican forces against Texan rebels at the Battle of Lipantitlán in the Texan Revolution.
Irish expatriates had a long tradition of serving as mercenaries in the military forces of Catholic countries, including in European countries after the Williamite War. In the decades leading up to the Mexican-American War many Irish fought in the South American wars of independence.
Service as a military unit
Formation and early engagements Present in the Mexican Army for the battles of Palo Alto and Resaca de la Palma were the Legión de Extranjeros (Legion of Foreigners); the men who would later make up the core of the Saint Patrick's battalion. Meanwhile, deserters were abandoning General Taylor's army on the Rio Grande. Riley and "a company of 48 Irishmen" manned Mexican artillery at the Siege of Fort Texas, which took place concurrently to the two other battles. Martin Tritschler, German Mexican and a Captain at the Battle of Cerro Gordo, is attributed with convincing a large number of German soldiers to defect from the U.S. occupying forces in Puebla, Puebla.
The first major engagement of the Saint Patrick's Battalion, as a recognised Mexican unit, was as an artillery battery in the Battle of Monterrey of 21 September 1846. Popularly they were called Los Colorados by the Mexicans because of their ruddy, sun-burnt complexions and red hair color. They were commanded by John Riley, an Irishman who had previously served in the British Army as a non-commissioned officer and possibly arrived in Canada in 1843 whilst serving in his British unit (the assertion that Riley was a sergeant in the 66th (Berkshire) Regiment of Foot is known to be inaccurate). Riley went on to join the U.S. Army in Michigan in September 1845. He deserted in Matamoros in April 1846. Upon meeting Mexican forces he was initially given the Officer rank of Lieutenant by General Pedro de Ampudia.
At the battle of Monterrey the proved their artillery skills by causing the deaths of many American soldiers, and they are credited with defeating two to three separate assaults into the heart of the city. Among their targets were companies led by such officers as Braxton Bragg, many of whose soldiers would end up in their own ranks later in the war. Their tenacity, however, did not affect the Mexican commanders' decision to capitulate and abandon the position.
Following the engagement at Monterrey, the grew in number, by some estimates reaching an enlistment of over 700 men. Forces re-assembled at San Luis Potosí and they had their distinct green silk flag embroidered there.
Buena Vista
They then marched northward after joining a larger force commanded by Antonio López de Santa Anna sent from Mexico City, the "liberating army of the North". At the Battle of Buena Vista (known as the battle of Angostura in Mexico) in Coahuila on 23 February, the Patricios became engaged with U.S. forces. They were assigned the three heaviest—18 and 24 pound—cannons the Mexican army possessed, which were positioned on high ground overlooking the battlefield, at the base of a hillside (just below what is now a gravel mine). They were later described as "a strong Mexican battery ... moved ... by dint of extraordinary exertions ... [that] commanded the entire plateau".
They started the battle supporting Mexican infantry by firing on U.S. lines as the Mexicans advanced on them, then later decimating an artillery battery directly opposite them on the battlefield (Washington's 4th Artillery, D Battery). A small number of were dispatched with a division commanded by Manuel Lombardini with the express purpose of capturing the 4th's cannons once the crews had been dealt with. As the division got close enough they charged the artillery battery, bayoneting whoever remained and routing the rest, leaving the attached free to haul away two six-pound cannons. These cannons would later be used by Mexican forces at the Battle of Contreras.
In frustration U.S. Commander Zachary Taylor, referring to the Saint Patrick's Battalion, ordered a squadron of the 1st Dragoons to "take that damned battery". In this task they failed, and, badly bloodied, were forced to retreat. At about 1 p.m. the covered a Mexican retreat as a disordered mass of infantry sought refuge during a lull in the fighting. The rode out the day in a costly artillery duel with several American batteries, which killed or injured roughly one third of them. General Francisco Mejia's Battle Report for Buena Vista described the ' as "worthy of the most consummate praise because the men fought with daring bravery." Several Irishmen were awarded the War Cross by the Mexican government for their conduct in that battle, and many received field promotions.
Re-organization and final battles Despite their excellent performance in a number of engagements as artillery, the much-reduced were ordered to muster a larger infantry battalion, as well as a cavalry unit, in mid-1847 by personal order of Santa Anna. It was renamed the Foreign Legion of Patricios and consisted of volunteers from many European countries, commanded by Col. Francisco R. Moreno, with Riley in charge of 1st company and Santiago O'Leary heading up the second. Desertion handbills were produced, specially targeting Catholic Irish, French and German immigrants in the invading U.S. army and stating that "You must not fight against a religious people, nor should you be seen in the ranks of those who proclaim slavery of mankind as a constitutive principle ... liberty is not on the part of those who desire to be lords of the world, robbing properties and territories which do not belong to them and shedding so much blood in order to accomplish their views, views in open war to the principles of our holy religion".