Called the Lossoth. They lived on the shores of the Ice Bay of Forochel.
These were a race of men who had learned to live in the severe colds of the far north.
They could make shelter using only snow. They could run on the ice with bones on their feet and they had carts without wheels.
The Lossoth were said to be a remnant of a First Age people known as the Forodwaith. Their origins remain shrouded in mystery: they might have been a race of Men travelling in the far north of Middle-earth, foiled by Morgoth and the EredLuin from crossing into Beleriand.
The Lossoth took in Arvedui, the Last King of Arthedain, as he fled from the Witch-king. They did not help Arvedui willingly, as they feared the Witch-king; but out of fear of their weapons and the pity they had for his gauntness, they agreed to help him and his men to survive the cold. Arvedui gave them the Ring of Barahir as a gesture of thanks; it was later ransomed by the Dúnedain.
At this point the Lossoth disappear from history. Some contact with them may have been established by the Reunited Kingdom in the Fourth Age.