Research Irish Battalion:Mexican-American War

Men of the San Patricio Battalion

 Translation: "In memory of the Irish Soldiers of the heroic battalion of San Patricio Maritres that gave their life for the Mexican cause during the unjust North American invasion of 1847." (names) "With gratitude from Mexico to the 112 years of your sacrifice. Sept 1955

The Saint Patrick’s Battalion (San Patricios) was a group of 700+ mostly Irish immigrant soldiers who defected from the U.S. Army to fight for Mexico in the Mexican-American War (1846–1848). Driven by nativism, anti-Catholic sentiment, and better pay, they fought fiercely but were captured at the Battle of Churubusco; 50 were executed by hanging in September 1847, making it the largest mass execution in U.S. history. These men were hung in three different locations. The courts-martial were held in Mexico shortly after capture in Tacubaya and San Ángel and during the Battle of Chapultepec. The hangings were held from 10 - 13 Sep 1847

Seventy-two to eighty-five prisoners were court-martialed. Some were considered not-guilty. Fifty were hanged. Those executed below agree with the plaque above. are listed were to include those sentenced to death.

The 1847 court martial records can be found: 

• National Archives and Records Administration (NARA) Office of the Judge Advocate General (Army), Record Group 153.
  
• Be sure to check the Regular Army muster rolls for 1846–1847

Charlotte. Newspapers 1845

Researchers can reconstruct the events from:

• court-martial summaries
• military orders
• correspondence
• newspaper accounts
• Mexican archival sources

There are also records in the: 

• Mexican archives (Archivo General de la Nación)
• Published trial summaries in military histories
• Chapultepec campaign records

Why This Post? Shameless Plug

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Who were the Irishmen of the San Patricio Battalion?

These Irish ancestors deserted the U.S. Army in 1846 to fight on the Mexican side in the U.S. Mexican War (1846-1848). Where are the records go these Irishmen who deserted the American side to join and serve with their Mexican "Catholic brothers.""

The Fraternalist, Missouri Valley Independent, 1 Oct 1955. St. Joseph, MO

A popular novel by Carl Kreuger, "Saint Patrick's Battalion" may also be of interest: 

The Solano-Napa News Chronicle, 19 Feb 1962, pg. 10

More References:

• The San Patricios: the Irish Heroes of Mexico
• The San Patricio Battalion: Irish and German Deserters in the Mexican-American War
• 30 HANGED AND 11 BRANDED, The Story of the San Patricio Battalion, Tom Mahoney 

Mexicans Became USA Citizens

Mexico had abolished slavery by 1829, and this war was viewed as an attempt by the U.S. to reintroduce slavery on "free" Mexican soil. It did succeed in expanding slave land by way of the annexation of Texas.

Brainerd Dispatch, 31 Jul 2018, pg. 6

Approximately 80,000 to 100,000 Mexican citizens (California and New Mexico) became "free persons" under U.S. law. This was not extended to enslaved American persons.

This War ushered in the Civil War.