He lost his battle with stomach cancer on Monday in Derby City hospital but will be remembered as one of the best managers England never had.
Current Forest boss Joe Kinnear led the tributes saying: "He is a football legend and as a manager he was simply a genius,"
Arsenal manager Arsene Wenger, who recently beat Clough's 42-match unbeaten record, told the Arsenal official website: "People use the word legend too freely but Brian Clough is a true legend of English football and his success in this country and in Europe is a legacy for which he will always be remembered."
Clough won the European Cup with Forest in 1979 and 1980 with victories over Malmo and Humburg respectively.
Nottingham-born striker Garry Birtles enjoyed a successful career on Trentside under Mr Clough and was as shocked as anybody to hear the news of his death.
He told SkySports: "When I heard, it was just like a bolt from the blue. Brian's son Nigel phoned me, he was upset, I was upset and it's just been a major shock.
"When somebody like Brian Clough dies, it's hard to explain how you feel. It's like a member of your family dying."
Nottingham Forest have announced they will hold a minute's silence before their Carling Cup clash against Rotherham on Wednesday and also in their Coca-Cola Championship game against West Ham United on Sunday. Players will also wear black armbands as a mark of respect, the same as players did in Manchester United's game against Liverpool on Monday night.
Everyone's thoughts are with his family and he will always be an absolute legend in the city of Nottinham. Rest In Peace.