The Singi River serves as the southern border of Tel'Durrsim, the arctic elf nation. It flows westward from Singi Lake to the Vaya Sea, forming a natural barrier against any potential land attack from the south. This natural defense is made even more effective by the need to circumnavigate the vast Singi Lake and traverse the northern fringes of the nearby active volcanic region. The high salinity of the lake and river also keeps them from freezing in the harshest of weather, making it near impossible for an army to march through.
The high salinity of the river makes it difficult for most species to establish a permanent home. During the few warmer months in the otherwise frozen region, brine shrimp spawn and salt algae bloom in the Singi River. These organisms go dormant when the cold weather returns.
Though not abundant, the resources of the lake and river are valuable to the Arctic Elves, and they make full use of them. The deposits along the shore give them easy access to salt, and they have mastered the art of using stills to separate the brine into salt and fresh water. During the warm season, they harvest both the brine shrimp and the salt algae to use as a food source. Despite their small size, the fried brine shrimp are an excellent source of protein for trail rations. The dried salt algae finds use as a meal garnish and can also be ground into a seasoning.
Many centuries ago, around 800 D.G., the elven nation of Syolrûn suffered a national schism that caused a minority to flee their homeland to the north to escape persecution. At first they settled along the southern banks of the Singi River, but soon found themselves under relentless attack from their former kinsmen. It was decided to attempt a daring crossing of the river at several points during a moonless night to cover their escape, which unfortunately resulted in many lives lost.
They settled again, this time on the north bank. The river only slowed the raids, but did not stop them. The fleeing elves fled further north, into the frozen taiga. They were forced to learn and adapt to survive, coming as they did from an almost tropical climate warmed by a nearby volcanic region. Over time, their culture evolved, creating a stark contrast between themselves and those they had left behind. They founded their nation of Tel'Durrsim and adopted the identity of "Arctic Elves", and began to refer to their southern cousins as "Savage Elves".
During this time, the arctic cold had expanded the frozen region farther south, possibly due to the inactivation of one or more of the northernmost volcanoes. The Artic elves reclaimed the Singi River as the cold spread south beyond it. The region immediately south of the Singi River became frozen and barren. The cold killed the heat-adapted flora and drove the creatures that lived there, including the savage elves, back south. The Arctic Elves chose not to expand beyond the river. They left the frozen area to the south as a protective buffer zone between themselves and their former kin.
Arctic elves that live in the far north, living off of brine shrimp and algae to survive. Definitely not how most people see your average elf!