It has come to my attention that since it's Cinco de Mayo, that I ought to be drinking Margaritas. It seems a bit odd in this day of anti-war protests, to be intoxicated because the French lost the battle of Puebla in 1862. While the French have lost (and for that matter won) many battles in their long history this rather straight forward victory of the underdog against imperialist invaders would be something to celebrate if one were one of those evil people who delights in the death of their fellow man. 

 That is Until you notice that the French went on to seize Mexico City and installed Maximilian Hapsburg as Emperor soon afterwards. There the French Stayed until American pressure forced them to leave in 1867. You'd think they'd want to celebrate the defeat and execution of Emperor Maximilian in 1867. (but then they might have to mention the aid the received form the Hated Gr*ng* bastards.)

According to Cathlicgauze this holiday was invented in the 60's by a holy alliance of Latino activists and Beer companies, which I suppose explains a lot. I mean as long as you can drink and expound upon the wonders of Latino culture (whether Mexican related or not) who cares if the history is lame. I mean Irish have St. Patrick's day and Italians have Columbus day, African-Americans ( Is that the proper term now? One never knows these days.) receive an entire month, I guess the Latinos didn't want to be left out.

Further info: French Intervention Wiki