Mourinho has signed a four-year contract and will return to the club where he won two Premier League titles, an FA Cup and two League Cups between 2004 and 2007.
Ron Gourlay, Chelsea FC Chief Executive, said: ‘I am delighted to welcome Jose back to Chelsea. His continued success, drive and ambition made him the outstanding candidate.
‘It is our aim to keep the club moving forward to achieve greater success in the future and Jose is our number one choice as we believe he is the right manager to do just that.
‘He was and remains a hugely popular figure at the club and everyone here looks forward to working with him again.’
Since leaving Chelsea in 2007, the 50-year-old Portuguese has worked in Italy with Inter and Spain with Real Madrid, lifting three league championships, two domestic cups and the Champions League.
Originally appointed at Stamford Bridge in 2004, immediately after winning Europe’s top competition with Porto, he quickly achieved success securing his first trophy for the club as early as February 2005, when we beat Liverpool 3-2 after extra-time in Cardiff to win the Carling Cup. We went on to win the league that season with a record 95 points and a record low of just 15 goals conceded in 38 games.
The club celebrated consecutive championships in our centenary 2005/06 season, secured with a 3-0 win over Manchester United in late April, and the next campaign we were able to add the Carling Cup with victory over Arsenal in Cardiff, and the FA Cup when United were beaten again in the first senior game at the new Wembley.
Mourinho departed by mutual consent in September 2007, going on to develop his already impressive CV by winning the Serie A twice in two years and the Champions League with Inter, before joining Real Madrid in 2010, where he lifted both La Liga and the Copa Del Rey, ending his stay in Spain yesteday.
He brings three coaching staff with him in Rui Faria, Silvino Louro and Jose Morais. Each carries the title of Assistant First Team Coach and will work alongside current first team staff Steve Holland, Christophe Lollichon and Chris Jones.
The new manager will be officially presented in a press conference at Stamford Bridge on Monday 10 June, further details of which will follow in due course.