Before you go out and do the American thing by using an immigrant holiday as an excuse to get stinko from corresponding ethnic drink (Guinness and whiskey for St. Patrick’s Day, tequila and Tecate for Cinco de Mayo…), take a moment to at least learn what the day is about and why it is celebrated.
Despite popular belief, Cinco de Mayo is not the day of Mexican independence. According to Wikipedia, “Cinco de Mayo is a national holiday in Mexico which commemorates the victory of Mexican forces led by General Ignacio Zaragoza over the French expeditionary forces in the Battle of Puebla on May 5, 1862.” See, what happened was, Mexico was already independent but owed copious amounts of money to Britain, France and Spain. Each of those countries (though at the time it may be more correct to refer to them as empires) sent troops to Mexico to demand their cash. The President of Mexico made arrangements with Britain and Spain, but France decided it was going to make a colony out of Mexico and invaded. Battles ensued.