After Zephyr had split the lands, the land with the most natural and old relics was left with the elves, beastmen, and other creatures that required this environment. This land was called Yamashi. Within Yamashi there were borders between areas. This was because most of the species still had a lingering hatred for each other because of the Great War. If it wasn’t for the demi-gods keeping watch, they would have started a new war right away. And so, all the creatures started their new (separated) lives on Yamashi.