Hrim (map) has existed as several independent regions for around fifty years, after the Last War, a conflict fought against the Winter Court in Nidaros, the Imperial capital (which is located within the borders of the Hrim free-states). The Winter Eladrin oversaw a vast empire through their vassal cousins which covered most of the known world, but specifically ruled from the north holdings of Hrim.
About forty years before the Last War began, the Empire sought to stamp out worship of the Old Gods - the spirits of nature that many of the natives of Vandalmál revere. Their way of life threatened, the druids and priests of local villages in Biarmia began organizing local adherents to protect their temples and shrines. This seed of rebellion attracted other elements within Hrim - Dwarven thanes tired of living under the boot of the Eladrin, Hobgoblin chieftains angry about efforts to curtail their nomadic way of life, and others - growing into an ever-widening revolt. Within the space of several decades, the once-mighty Winter Eladrin saw their grip on Hrim shattered. In a last, desperate attempt to maintain control of Nidaros and the empire, the Winter Eladrin unleashed some sort of fell magic to try and repel the rebels at their gates, but the results were horrific. These spells are still functioning, rendering much of the city uninhabitable even fifty years later, and no one has seen a member of Winter Court (nor a Winter Eladrin) since.
The other Eladrin, unable to mount an effective assault on Hrim, sought an armistice with the organizers of the rebellion. Control of the remaining holdings of the Empire fell to the Summer Court in Einmanudr, while the inhabitants of Hrim were left to seek their own fates and fortunes. As a result, the political structure of Hrim varies from region to region.