The dance of the Gods 
According to the Norse Vikings, the colors of the auroras were nothing more than the sun reflected from the shields of the Walchirias. They were the virgins sent into battle by Odin to choose the heroes who were to die and lead them to the  Valhalla . 
So the glows in the sky signaled that the  Valkyries  they were "at work", an indication of a battle taking place somewhere. Once in the  Valhalla , the  Valkyries  they carried horns full of beer to the  Einheriar  (warriors killed).