Celtic chairman Ian Bankier has claimed that new manager Brendan Rodgers was the "outstanding candidate" in the club's hunt for Ronny Deila's replacement.
The Northern Irishman, who has been out of work since getting sacked by Liverpool in October, has signed a 12-month rolling contract.
In his managerial career, which includes spells at Watford, Reading, Swansea City and Liverpool, Rodgers has won one trophy - the Championship playoff final.
Celtic chairman Ian Bankier told the club's official website: "We are delighted to welcome Brendan to Celtic as the club's new manager. As expected, there was huge interest in the position of Celtic manager but we believe we have chosen the outstanding candidate to take the club forward.
"Brendan is a man with a tremendous pedigree in football management, he is someone who knows all about Celtic and someone who has a real passion for Celtic. He is also a manager who we believe has the talent, the drive and the determination to bring continued success to the club.
"We are sure Brendan will receive a fantastic welcome from our supporters and we now look forward with real excitement towards next season as we tackle the many challenges ahead domestically and in Europe."
Chief executive Peter Lawwell added: "Brendan is a highly-sought after manager and we are pleased that we have been able to bring such a high calibre individual to Celtic. He has a huge and genuine affection for the club.
"I know Brendan feels privileged to be named Celtic manager and I know he will give us everything he has to be successful at Celtic. Above all, he will bring huge experience, knowledge and ability to the role.
"We wanted to bring one of the biggest and best names to the club to match our own aspirations and those of our supporters - we believe, in appointing Brendan, that we have done this. We have appointed a special manager and we are sure he can bring some special times to Celtic."
Deila leaves the club having guided the team to Scottish Premiership glory in both of his seasons in charge, as well as the Scottish League Cup.
