This came a day after the Blues parted ways with Frank Lampard as their manager following Chelsea’s recent poor run of form.
Tuchel had been out of work since being sacked by Paris Saint-Germain last month after spending two-and-a-half seasons with the Ligue 1 giants, where he won back-to-back league titles, the French cup and league cup.
Prior to his adventure in France, the German spent seven seasons in the Bundesliga coaching Mainz and Borussia Dortmund.
Tuchel guided Mainz to the Europa League and while at the Signal Iduna, he won the German Cup with the Black and Yellows.
‘I would like to thank Chelsea FC for their confidence in me and my staff,” Tuchel said right after signing for Chelsea.
‘We all have the greatest respect for Frank Lampard’s work and the legacy he created at Chelsea. At the same time, I cannot wait to meet my new team and compete in the most exciting league in football. I am grateful to now be part of the Chelsea family - it feels amazing!’
Director Marina Granovskaia added: ‘It is never easy to change Head Coach in the middle of the season but we are very happy to secure one of Europe’s best coaches in Thomas Tuchel. There is still much to play for and much to achieve, this season and beyond. We welcome Thomas to the Club.
Tuchel becomes the first German tactician to coach Chelsea and will be reunited with Christian Pulisic and Thiago Silva who he trained during his spells in Dortmund and Paris respectively.