The 23-year old Norwegian midfielder has joined the Hoops from homeland club Stromsgodset on a three-and-a-half-year deal for a fee of £2million and was delighted to have finally clinched the move.
"I talked with some of the guys in the national team and they said Glasgow is fantastic," the Norway international told the club's official website.
"The fans are unbelievable and the club is one of the biggest in the world so it was a pretty easy choice. And I'm looking forward to playing at Celtic Park.
"When you're young, you just dream about something like this happening. The club is so big so it's an unbelievable feeling to be here.
"As a Norwegian youngster, you dream about playing for the national team and also for a big club in Europe, and now I have the chance to achieve both of these things, so I'm very happy.
"The league is better in Scotland, and there are no clubs in Norway who are as good as Celtic, but the type of football is quite similar. They have the passion, but this very many steps up.
"I've watched some games and when I heard Celtic were interested in me I watched a few more games. I've seen many of the Champions League games on TV and it looked fantastic.
"I'm a passing player, a possession player, but I'm also a winner - I like to win, so the culture here is perfect for me and Celtic are a team who always try to play football so I think it will be a perfect match."
For breaking stories and all the great banter like us on Facebook: facebook.com/tribalfootball