Stewart, with his distinctive spiky blond hair and raspy voice, dominated pop charts during the 1970s and 1980s with hits like "Da Ya Think I'm Sexy?" and "Young Turks", notching up more than 250 million record sales worldwide.
He also made headlines for a prolific love life that included relationships with a string of models and actresses including Britt Ekland.
Despite his landmark birthday, Stewart says he has no plans to retire.
"I love what I do, and I do what I love. I'm fit, have a full head of hair and can run 100 metres (330 feet) in 18 seconds at the jolly old age of 79," he wrote last year.
The star will play the legends slot at the famed Glastonbury music festival this summer.
Although his forthcoming European and North American tour dates will be his last large-scale project, he has said he plans to concentrate on more intimate venues in the future.
He will headline a new residency in Las Vegas from March to June.
A tour is also slated for 2026 for Swing Fever, the album he released last year with pianist and ex-Squeeze band member Jools Holland.
As he has approached his ninth decade, Stewart has also made headlines for quirkier reasons such as his passion for model railways and his battle with potholes that have prevented him from driving his Ferrari near his home in eastern England.
The singer, who was knighted by Queen Elizabeth in 2016, has been married three times and has fathered eight children. His third wife is model and television personality Penny Lancaster.
From London to global star
Stewart's story began in north London on 10 January 1945, when Roderick Stewart was born into a middle-class family.
After a "fantastically happy childhood", he developed a love of music when his father bought him a guitar in 1959, and he formed a skiffle band with school friends a year later.
He joined the band Dimensions in 1963 as a harmonica player, exploring his love of folk, blues and soul music while learning from other artists such as Rolling Stones frontman Mick Jagger in London's blossoming rhythm and blues scene.
Stewart's career took off in 1967 when he joined the renowned guitarist Jeff Beck's eponymous new band, which also included future Rolling Stone Ronnie Wood, allowing him to develop his raw and soulful vocal style and stagecraft while exposing him to a US audience.
He and Wood took up the offer to join mod pioneers Small Faces following the departure of their singer Steve Marriott in 1969 -- the band soon changing its name to The Faces -- shortly before Stewart released his debut solo album.
It was his 1971 third solo release, "Every Picture Tells a Story", that confirmed him as one of the world's most successful artists, reaching number one in Britain, Australia and the United States, where it went platinum.
The album helped define Stewart's rock/folk sound, featuring heartfelt lyrics and heavy use of unusual instruments such as the mandolin, particularly prominent on the album's standout hit "Maggie May".
"I just love stories with a beginning, middle and end," he once said.
'I had the last laugh'
Focusing on his solo career after 1975, Stewart's "Da Ya Think I'm Sexy?" released in 1978 was not to everyone's taste.
"Once the most compassionate presence in music, he has become a bilious self-parody -– and sells more records than ever," Rolling Stone magazine said in 1980.
Never one to be cowed by the critics, Stewart defended this phase, telling an interviewer that audiences "absolutely love it, so I had the last laugh".
Richard Houghton, author of the book "Tell Everyone -- A People's History of the Faces" said that Stewart had "possibly the most distinctive voice in rock music".
The singer had successfully combined writing classic songs of his own such as "Maggie May" or "You Wear It Well" with taking other people's songs -- from Bob Dylan to Tom Waits -- and making them his own .
More recently, there had been four albums of the "classic songs of the 1930s from his Great American Songbook catalogue".
Houghton said audiences could expect to see plenty more of Stewart.
"He's like any entertainer. He loves the spotlight. He's not going to sit at home watching the television when somewhere around the world there's a crowd wanting to hear him sing 'Mandolin Wind' or 'First Cut Is The Deepest' one more time.
"Rod will keep singing until the day he drops," he added.
