But IIRC the way I got it (did a semester down there) was that the decline around 900-1100 ad of the mayan centralized city-states was due to possibly climate change/drought/agricultural catastrophe or possibly the collapse of Teotihuacan created a domino effect, sort of the like the stock market collapse here in 1929.
But this was just the "urban civilization/trade centers" part of mayan culture, the people themselves survived scattered into smaller polities.
Regardless of the much-disputed causes, the decline of the big city-states supposedly might have actually helped ensure the survival of the maya peoples relatively intact ethnically after Spanish conquest, because they were more dispersed in the inaccessible parts like Quintana Roo (Yucatan was almost all dense jungle; still is pretty dense.) & the Guatemalan Highlands
Chichen & Uxmal & Coba if I recall correctly were all very much thriving in the post-classic period. Mayapan did get sacked in a revolt I think though. But the last Mayan city-state at Tayasal (Guatemala,founded by Itza Maya ) didn't fall to spanish colonial control until around 300 years ago.I know that one of the Bishops in charge of converting the maya ordered some important mayan codexes destroyed. (EEK!)
It's been my understanding that the great Mayan cities might have disappeared under the jungle canopy & Spanish rule, but the Maya people (genetically, linguistically & culturally related to the people who built the pyramids) are still there.
But I'm certainly no expert, hopefully someone on FR with better credentials will settle the question for us here.I have a feeling we'll be seeing plenty of threads about this because of the movie.