In Old Norse culture, the sun was always seen as a deity, a higher power that gave Earth life & light so all could thrive. These elements given to us by the sun are obviously very real, and without it, we would all surely cease to exist. It was, and still is, by many seen as a Goddess. In Northern Europe, this Goddess was named Sól.

Sól was celebrated mostly during the MidSummer festivals. This festival was to praise her majestic radiance and all the good her energy has bought the people, the animals and the land. During MidWinter she was called during a great sacrifice, known as a Blót (Blood Sacrifice), during Yule, where they would call for her return.

You need to remember that back in the old days of Northern Europe during winter many of the people you knew would die from the cold and hunger. The nights were long and cold. The return of Sól was the most important thing in their lives at the time, so it's clear just how important this Deity is to the Norse faith. 

In 2 books from the 13th century, the Poetic Edda and the Prose Edda, Sól is described as the sister of the personified moon, Máni. They both mention that she rides her horse-drawn chariot around the world, until she is devoured by the great wolf Hati Hróðvitnisson, meaning 'He who Hates', during Ragnarok (the twilight of the Gods).