Sept 16 (their independence day) is probably the most important secular holiday in Mexico. May 5 seems to be a big deal only in tourist areas and border cities, where it's mainly done for the benefit of Americans who want to party in Mexico.
There are several other examples of relatively minor holidays that have been inflated in prominence for purely commercial reasons. It's my understanding that Hannukah is (or rather was) a very minor Jewish holiday compared to Passover etc, but was given great prominence so that Jewish Americans could also partake in the frenzy of consumerism in December.
That is true. Chanukkah is a minor holiday on a par with Purim, yet it's been blown up into a major holiday to the point that non-Jewish calendars always include it, even as they completely ignore Shavu`ot and Sukkot (and Purim, which has never become the "Jewish St. Patrick's Day").
This is for several reasons. First, the solar new year (winter solstice) is a universal celebration and lies at the heart of many of the holidays that have been celebrated at this time of year. Chrstmas itself is actually a relatively minor chrstian holiday (the really big chrstian holiday is the other one . . . the one that often falls around Pesach). Yet it is chrstmas that has become the great annual celebration marking the turning of another year. "Pascha" falls in spring, which isn't nearly the marker in the year that December is. So the solar new year inflated chrstmas into a major holiday just as chrstmas later inflated Chanukkah into a major holiday.
Another reason is that the origins of Chanukkah are not to be found in Protestant versions of the chrstian bible. This makes it a holiday that the "rednecks" didn't learn about in Sunday school, and secular but identitarian Jews get to instruct those graduates in a post-Biblical holiday.
Finally, the war to restore unadulterated Torah observance bears a false but superficial resemblance to modern post-"enlightenment" struggles for "religious freedom" (ie, total religious relativism). Actually, the origins of Chanukkah took place within a totally Theocratic context, not one of modern multiculturalism. Plus even more than the Greeks, the Chashmonaim fought against liberal Hellenistic Jews in what was primarily a Jewish civil war (fundamentalists vs. liberals, and the fundamentalists were the good guys). The war begian when Mattityahu, Judah's father, saw a fellow Jew "exercising his right" to worship in a forbidden manner, at which point he (Mattityahu) cut his head off. Not exactly the best start for a story allegedly about integrating neighborhoods or coming to realize that all religions are equally fairy tales.
I once cynically described American liberal Jews' Chanukkah as being the celebration of the anniversary of when Thomas Jefferson received the "Bill of Rights" on Mt. Rushmore.
At any rate, it's a very minor holiday. The only real commandment connected with it is lighting the lights and publicizing the miracle. There are additions to the `Amidah (the main Jewish prayer) and the prayer after meals, but in the same places that the Purim additions occur, and not the place where special prayers are inserted for the actual Torah-authorized holidays.
Oh, and there is a special Torah reading each day, with Hallel recited each morning. But that's about it. It doesn't have a tractate of the Mishnah dedicated to it like Purim does.