Spurs connection clinched Campbell deal for Newcastle
Campbell told nufc.co.uk: "At this stage of my career I couldn't have wished for a better move. To join a club such as Newcastle United, with its proud tradition, heritage and magnificent support, is absolutely tremendous for me.
"I'd like to thank Chris Hughton for putting his faith in me and aim to repay him and the supporters by giving everything I possibly can to help re-establish this great club in the top tier of English football.
"I just want to play and can't wait to get started. There's a real buzz about the place and that's great. I've played at St James' Park numerous times and always found it a fantastic place to play. There's always a tremendous atmosphere."
Campbell is also looking forward to working again with Chris Hughton, who was a coach at Tottenham when the centre-back came through the ranks, and his assistant Colin Calderwood.
"Chris will focus everyone together and get the team ready for the season," added Campbell. "It's nice seeing Colin Calderwood, too, having played with him at Tottenham."