Keegan is fondly remembered for his achievements as a player, winning two Ballon d'Ors and featuring for Scunthorpe, Liverpool, Hamburger SV, Southampton and Newcastle.
A glittering playing career saw him clinch the Ballon d'Or twice, as well as three First Division titles, an FA Cup, European Cup, two UEFA Cups and one Bundesliga.
Off the pitch, 'King Kev' managed Newcastle for five years from 1992 to 1997, enjoying a successful spell with 138 wins from 251 fixtures, before returning to the club over a decade later to guide them to a 12th-place finish in 2008.
Keegan enjoyed further managerial spells at Fulham and Manchester City.
He also made 63 appearances for England before going on to manage the Three Lions and help them qualify for Euro 2000 in 18 months at the helm.
"It is with immense sadness that we announce that Kevin Keegan has passed away at the age of 75," his family said in a statement.
"Kevin had been battling cancer and was surrounded by his wife and daughters in his final moments.
"A double Ballon d’Or winner, Kevin was a much-loved husband, father and grandfather.
"The family would like to thank Kevin’s incredible medical team for all their support.
"This is a hugely difficult time, and they are requesting space and privacy."
Two of Keegan's former clubs, Newcastle and Liverpool, face off on the opening weekend of the 2026/27 Premier League season.
The Magpies have confirmed that, when the time is right, they will be looking into a way to pay tribute to Keegan's life and legacy.
"We are devastated to learn of the passing of Kevin Keegan, one of the most iconic, influential and deeply loved figures in our club’s history," Newcastle wrote on their website.
"Kevin was more than a legendary footballer and manager. He was the beating heart of Newcastle United for generations of supporters.
"As a player, he brought world-class talent, ambition and belief to St. James’ Park, helping to transform perceptions of what Newcastle United could be.
"As a manager, he ignited our city. Kevin gave supporters hope and pride, and led a team whose style, spirit and passion captured the imagination of football fans around the world. He was so much more than an Entertainer.
"Above all that, Kevin forged an extraordinary bond with Newcastle, built on the roots of his father, Joe. He understood our people. He embraced the North East with a passion that was genuine and unwavering, and in return, he earned his rightful place in the hearts of millions."