Here's a great review for Michael Hogan's "The Irish Soldiers of Mexico."

"Michael Hogan, author of the exceptional THE IRISH SOLDIERS OF MEXICO —a 1998 edition that is now available in a 2011 e-book and paperback formats— and a foremost expert on the US-Mexico conflict, achieves what very few scholarly historians can accomplish: examine historical events and seamlessly synthesize those events into a prose that is readable, informative, thought-provocative, and perspective-changing.

Hogan’s chronicles of the famed San Patricios, a battalion of mostly Irish Catholic soldiers who deserted the US Army to fight for Catholic Mexico, with an attention to fact and historical detail. Yet at the same time that the reader learns of this heroic group of fighters who valiantly defended the Mexican side even during defeat, Hogan weaves some of the most concise and comprehensive history of the war, from its origins of new Texans rebelling against the Mexican government and exploiting the United States’ belief in expansion to the chronicles of a bloody struggle that claimed thousands of lives."