The St. Patrick's Battalion: The Irish Who Fought for Mexico

Introduction

Few people outside Mexico and Ireland have heard of this Mexican army unit that helped defend the country during the Mexican-American War of 1846-48. Although eventually named after St. Patrick, the body was neither entirely Irish nor totally Catholic. Nevertheless, its most famous commander, John Riley, was Irish as were many of the men who served in the unit. Furthermore, most of the volunteers were actually men who had deserted from the American ranks and then cast in their lot with Mexico. This makes the St. Patrick's Companies - they were only raised to a battalion at the end of the war - fairly unique in military history. Other countries have had their foreign legions, but Mexico is one of the few that has managed to recruit soldiers from the enemy's forces in sufficient numbers to keep two companies of just over a hundred men each in the field until the war ended.

Forming The Unit

The origins of the St. Patrick's Battalion are not hard to fathom. In early 1846 as war with the United States loomed, the Mexican military commanders in the north made a concerted effort to entice American soldiers to desert. Leaflets were produced which offered land to any man who would change sides, and it was also pointed out that the pay they could expect in the Mexican army was higher than they were receiving in the American ranks. Finally, rapid promotion, and thus higher pay and a land grant at the end of their service, probably also played its part. So even before the war began, a steady trickle of men were crossing over the lines and taking up the Mexican offer. Once the war began, and until the last American soldier left Mexico after it was over, the Mexicans continued to offer places in their army to anyone who would desert the invaders' ranks.