Steve Harley, the 1970s British rock star who topped U.K. music charts with the single “Make Me Smile,” died on Sunday. He was 73.

He died at his home, his family said on Facebook. No cause was given but Mr. Harley had announced last month that he would step away from the stage to undergo treatment for cancer and previously canceled several concerts scheduled for this year.

Mr. Harley was the frontman of the band Cockney Rebel, which he formed in the early 1970s.

His biggest hit was the 1975 single “Make Me Smile,” in which Mr. Harley’s even-keeled vocals and melancholic lyrics cruise over instrumentals bearing the optimistic sound distinct to bands of the era. The song hit the top of the British charts in February of that year.

Other songs found success outside of Britain.

“Sebastian,” a single featured on the band’s debut 1973 album, “The Human Menagerie,” wound up being a No. 1 hit in Belgium and the Netherlands, according to Mr. Harley’s website.

In 1986, Mr. Harley and the singer Sarah Brightman recorded the original “Phantom of the Opera” for the musical of the same name by Andrew Lloyd Webber.

Steve Harley was born on Feb. 27, 1951, in London and was the second of five children, according to his online biography. His mother, who sang jazz and swing in the 1940s, offered Mr. Harley one of his earliest introductions to music.

“She sang around the house when we were kids,” he said in a 2022 interview for the Tim Quinn YouTube channel, comparing his mother’s voice to the British vocalist Anne Shelton.

When he was a child, his mother would sing along to Buddy Holly and other 1950s pop singers who would play on the radio, he said in the interview.

A full list of survivors was not immediately available.

An illness and surgeries kept Mr. Harley rotating in and out of the hospital as a child. At age 12, while recovering from surgery, Mr. Harley found an affinity for the works of D.H. Lawrence, Ernest Hemingway and other authors and took a liking to Bob Dylan’s music, according to his online biography.

These artists moved a young Mr. Harley to realize that his life would likely be “preoccupied with words and music,” his website said.

He indeed became preoccupied with words in the late 1960s and early 1970s as he pursued a career in journalism, working for several daily newspapers in the U.K.

Around the same time, his life as a singer was born in London nightclubs where he would perform free and met his eventual Cockney Rebel bandmates, with whom he struck the band’s first record deal in 1972.

A prolific performer, Mr. Harley’s singing days stretched into his final years. He took the stage as recently as 2023.