"German football is in mourning after the death of Christoph Daum. The former Bundesliga-winning coach has died at the age of 70 from long-term cancer," the DFL said in a statement.
Daum, who also coached Cologne and Bayer Leverkusen before winning titles in Turkey and Austria, went public with his cancer battle in October 2022, saying he wanted to raise awareness of the illness.
"I try to live my life and not let cancer dominate," Daum said.
As was typical during his decades-long career in football, the former coach was bullish in his fight, saying "cancer chose the wrong body".
"Christoph Daum has left a significant mark on German football," German FA (DFB) boss Bernd Neuendorf said in a statement.
"He was a pioneer of the modern game and he was combative and passionate until the end."
A colourful character, who missed out on the chance to coach Germany after failing a cocaine test, Daum twice guided Cologne to runners-up spots in the Bundesliga in the 1980s, both times behind Bayern Munich, before taking Stuttgart to the title in 1992.
Moving to Leverkusen, Daum finished runners up three times, losing the title to Bayern on the final day of the season with a loss at Unterhaching, when a draw would have brought the club a debut top-flight victory.
Bayern Munich proved to be his nemesis and the frequently outspoken Daum often butted heads with Bayern powerbroker Uli Hoeness.
After Euro 2000, Daum agreed to take over the head coaching position with the German national team but was implicated in a cocaine scandal before starting the job, fuelled by public accusations from Hoeness.
To prove his innocence, Daum offered to take a hair test -- but the results found traces of cocaine. The DFB's contract with Daum was torn up, forcing the coach abroad.
Having already won the Turkish title with Besiktas in 1994, he won two more with Fenerbahce, and also picked up a winners' medal in the Austrian Bundesliga with Austria Vienna.
Daum's final coaching post was as manager of the Romanian national team in 2016-17.
Hoeness was one of the first to offer condolences on Sunday, revealing the two "made our peace years ago", adding "the news of his death affects me deeply".
In May 2024, Daum celebrated former club Leverkusen's league and cup double, with the club breaking through for a top-flight title for the first time.
Leverkusen coach Xabi Alonso dedicated the title victory to Daum, saying the victory "must be shared and enjoyed" with the former manager.
