What is la Gritería? What is Purísima?

Today was the national holiday of Purísma.  From what I can tell, this may be a tradition unique to Nicaragua.  I'm not going to make any claims of fully understanding Catholic theology on this one, but this is the celebration of the Immaculate Conception of Mary, that is, when Mary was conceived, without Original Sin.  This kind of a holiday can highlight the tension between Catholics and Evangelicals, so I'll try my best describe what I observe in this tradition. Since I'm new to this, I also might be missing some significant parts that I'm unaware of.

For nine days leading up to Purísima, Catholic churches are gearing up.  Streamers are stretched across roads, roads are painted with messages, the main street downtown is decorated with extravagant "altars" or immobile floats of sorts.

The "main event" for Purísima is actually la Gritería, celebrated the evening before Purísima, which is the national holiday on December 8. La Gritería, or the Calling Out, refers to the question: "Who is the source of such happiness?" to which others call back, "the Conception of Mary!"

While we've been hearing firecrackers going off over the last number of days, around 6:00 they start blasting off all around the city.  Lots of noise.  And lots of car alarms going off as a result as well. Folks start to make their way out into the streets with their backpacks and bags.  There would definitely be some similarities at this point with trick-or-treating.

Generous families willing to share their resources with their visitors will decorate and set up a figure of Mary.  Then others come by to sing traditional songs and then are given gifts of food, household items, and candy.  The hosts let in a family at a time to come in, sing, receive their gifts and move on to another home.

Then we start to hear some snare drums coming down the street.  These accompany the Gigantonas, costumed people on stilts. I understand that these guys will share a silly "couplet" rhyme for a tip, but I haven't seen (or paid) for this as of yet. (These gigantonas come around at other random times as well, so it's possible that they have less to do with la Gritería and Purísima and more to do with the energy of the event and the possibility of earning tips.)

All this time the firecrackers and car alarms continue in a noisy harmony.  At midnight, these reach their grand finale for the night. (Remarkably, our kids sleep through it.) Today, which was Purísima itself was a very quiet day in the city with most stores closed and few people out and about.  However at 12:00 pm and 6:00 pm the coordinated firecrackers were going off again, and I believe that we'll hear them at midnight again tonight.