The 23-year-old forward lost his place in the starting line-up at Stamford Bridge after Thomas Tuchel replaced Frank Lampard as manager.
The deal for Tammy Abraham, who was Chelsea's joint top scorer last season, includes a buy-back clause set at £68m.
Drogba netted 164 goals in 381 games for Chelsea and won four Premier League titles, four FA Cups and the 2011-12 UEFA Champions League.
Gianluigi Donnarumma denied Bukayo Saka and Jadon Sancho, while Marcus Rashford hit the post as Italy edged a penalty shoot-out in the Euro 2020 final.
After enjoying massive success at Wolves, Nuno joins Spurs on a two-year deal, bringing an end to their long search for Jose Mourinho's replacement.
Spaniard Rafael Benitez, who is best known for his success at Liverpool, is now manager of their biggest domestic rival Everton.
De Bruyne’s Chelsea career never took off as he left for Wolfsburg before returning to the Premier League with Manchester City.
As he turns 43, let us look back to the day when Frank Lampard scored twice, and won Chelsea the 2004-05 Premier League title.
Mourinho was signed by Italian club Roma just 15 days after being sacked by Premier League club Tottenham Hotspur.
After helping the club win its first Serie A title in over a decade, the 51-year-old left the Italian giants in a shocking move.