The striker became the Canaries' seventh signing of the summer as manager Chris Hughton reshapes his squad ahead of the new season, joining on a three-year-deal.
|80/1||Gary Hooper is 80/1 with Bet365 to be the Premier League's top scorer
"The problem is nobody really gets a chance for England when they're playing in Scotland.
"I know Fraser Forster got in last season but, after the Champions League run was over, he found himself out of the England squad again.
"If I'd managed to get in the England squad with Celtic, it would have changed my thinking completely but it didn't and that's why I knew I had to go prove myself in the English Premier League.
"It was hard to leave Celtic but it was something I felt I had to do."
Hooper scored 82 times in 138 Celtic appearances, having signed from Scunthorpe United in July 2010.