I recently went to a gathering for the NEARA organization and heard some talk about a "theory" regarding a lost Mayan colony in the area of present-day Georgia called Itsapa that apparently featured in a Spanish map dating from the early 1500s. Other than that, though, I wasn't able to find much else about the topic. To be honest, I'm pretty skeptical, although I will admit I would not consider myself an expert on the subject.
Might anyone specializing in Native American or Mesoamerican culture enlighten me on this? Furthermore, I'd like to ask: how much influence did the Maya exert outside of their main sphere of influence (I assume it was limited to just the Yucatan) and how possible is it that they would form trade colonies outside of that area?.
Congratulations! You've stumbled upon the world of Richard Thornton, who took the plunge into pseudo-archaeology sometime in 2011, if not earlier (honestly I'm unfamiliar with his earlier Ancient Roots series but I haven't heard any complaints about them either, most of the criticism for Thornton picks up in 2011).
The story of Itsapa goes back to December 2011, when Thornton published "Ruins in Georgia mountains show evidence of Maya connection" at the examiner.com. His 'work' on the topic has never appeared in any peer-reviewed journal. The story went viral, unfortunately, despite being opposed by actual archaeologists who had studied the site--Mark Williams and Johannes Loubser, mainly.
A year after the examiner article, the Itsapa story became the topic of the premiere episode of History Channel's "America Unearthed," a show that has never met a fringed theory it didn't like. Shortly after that, Thornton published a book on the topic, Itsapa: the Itza Mayas in North America, again still operating outside peer-review.
In short, Itsapa is fringe theory propagated by one man who has been very successful at spreading his idea around online and through dubious television networks.