Worship of Uller
Numerous temples were dedicated to Uller in the North, and on his altars, as well as on those of all the other gods, lay a sacred ring upon which oaths were sworn. This ring was said to have the power of shrinking so violently as to sever the finger of any premeditated perjurer. The people visited Uller’s shrine, especially during the months of November and December, to entreat him to send a thick covering of snow over their lands, as earnest of a good harvest; and as he was supposed to send out the glorious flashes of the aurora borealis, which illumine the Northern sky during its long night, he was considered nearly akin to Balder, the personification of light.
According to other authorities, Uller was Balder’s special friend, principally because he too spent part of the year in the dismal depths of Nifl-heim, with Hel, the goddess of death. Uller was supposed to endure a yearly banishment thither, during the summer months, when he was forced to resign his sway over the earth to Odin, the summer god, and there Balder came to join him at Midsummer, the date of his disappearance from Asgard, for then the days began to grow shorter, and the rule of light (Balder) gradually yielded to the ever encroaching power of darkness (Hodur).