Been thinking about our Oltec problem and I have a suggestion that may work or give someone further ideas.
Wilhelm and I have talked about having the Oltecs emerge out of Davania and if we use this we could have Oltecs around the Adakkian Sound living in tropical forests roughly at 35° N latitude. Here's my thoughts:
The Oltec Problem
by Sheldon Morris5000 years ago they expanded out and through isolation developed many unique tribes. One of the mightiest of these tribes, known as the Oltecs, began to conquer neighbouring tribes. Thus, this grouping of people are collectively known as Oltecs with all others being lost to history, except the rival tribe known as the Azcans.
These two groups competed for 500 years. During this time, villages were frequently razed and tribes moved often. Some crossed the Serpent Strait and followed the south and west coasts. The Karimari also arrived at this time and the clashing with the Oltec and Azcan polarised the two groups; the former holding the Peninsula's interior and the latter staying to the coastal regions.
Oltecs and Azcans reach the western shores now known as the Konumtali Savannah, but during their time it was a woodland moderated by warm ocean currents. The Oltec faction are driven a little further into the foothills of the Black Mountains while the Azcan faction discover mysterious earth farther inland; the ground would never freeze even in the harshest of winters. Geothermic activity below the surface allow life here to thrive.
Then the GRoF altered everything. The tropical forests around the Adakkian Sound dried up as vast deserts on either side began to form. Even tribes that had migrated outside this area began to change their culture as their environment changed around them. Immortals noticed this rapid changing of such an ancient culture and transported them to the Hollow World to preserve it and the people.
On Brun, the Oltecs and Azcans experienced a similar drying up of their environment. The land that wouldn't freeze now started to burn with its heat and would not support any life. They were forced to move or die. Travelling east they struggled against a dying land behind them and then retreating glaciers in front of them.
Then their shamans saw a great wall of land over a 1000 feet high with plant life that was actually growing around it instead of dying. They sought refuge here among the caves.
Some Oltecs travelled west instead and met other peoples and formed other cultures.
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There's my take on the situation at present. I think this could work out but I'd like to know if there's any problems with it that I can't see at the moment.