The hall was a center of social interaction for the Norse, especially Norse rulers.  They gathered there, held court, ate, told stories, drank beer.  It was a display of a king’s, or thane’s, wealth if he had a splendidly decorated hall.

“I was nurtured
in the kingly hall,
I was the joy of many
in the council of men.
Life I enjoyed,
and my father’s wealth,
five winters only,
while my father lived.”

-- The Poetic Eddas, Oddrun’s Lament