The Republic of Tasavalta (🔊) is the earliest human nation on Eamon known to modern historians, founded over 20,000 years ago in what was then the wooden coastal hills of southeastern Addar. It was established by a hero from the north, known in the legends only as Nuorgam ("Northman"), who drove out the evil creatures inhabiting the region using the Sword of Inari, a weapon imbued with divine power, and created a safe and prosperous haven for the region's people.

Two centuries later, with the waking Great Old Ones nearing the peak of their power, neither Nuorgam nor the Sword of Inari could be found and the land and its people were left defenseless against the Ruin. Hordes of monstrous creatures swarmed the nation, killing every inhabitant and razing every structure. Xor'urr, greatest and most vengeful of the eldritch gods, went further and broke the very ground that Tasavalta stood on, collapsing many thousands of square miles of land into the sea and allowing the waters to rush inland, forming what is now the long western arm of the Gulf of Hedrin.

Tasavalta now exists only in legend and a handful of rare artifacts, some of which are held by the Museum of Natural History in Evenhold. The disaster prompted Tasavalta's few survivors, along with the inhabitants of surrounding areas, to quit the region and migrate to new lands in the north and west.