Mourinho has previously managed teams including FC Porto, Internazionale, Chelsea, Real Madrid and Manchester United.
Mourinho will take over from Mauricio Pochettino, who was sacked on Tuesday.
“I am excited to be joining a club with such a great heritage and such passionate supporters,” said Mourinho in a statement released by the Premier League club. “The quality in both the squad and the academy excites me. Working with these players is what has attracted me.”
Daniel Levy, the chairman of the club, said: “In José we have one of the most successful managers in football. He has a wealth of experience, can inspire teams and is a great tactician. He has won honours at every club he has coached. We believe he will bring energy and belief to the dressing room.”
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