Singer and mentor to The Beatles;

Born: May 21, 1940; Died: February 16, 2013.

Tony Sheridan, who has died aged 72, was a pop singer and guitarist who enjoyed moderate success in the early 1960s but was ultimately eclipsed when his backing band became the most famous group in the world.

Tony Sheridan and the Beat Brothers had a hit in Germany in 1961 with My Bonnie, an upbeat version of the traditional Scottish folk song My Bonnie Lies Over the Ocean.

It was released in the UK a few months later but failed to chart, although it played a key role in the subsequent success of the band, who had reverted to the name under which they would become world famous.

It is the stuff of legend that a young rocker called Raymond Jones walked into Brian Epstein's record shop in Liverpool and asked for My Bonnie. "It was made in Germany - It's by a group called The Beatles ... You won't have heard of them."

Epstein discovered the group played regularly just along the road at a place called the Cavern and decided he would check them out.

Sadly for Sheridan it is a history in which he became little more than a footnote, though he was the bigger name in those early days in Hamburg.

He was only a few months older than John Lennon, but had been on tour and on television. He became a role model, influenced them as performers and introduced them to some of the American rock and R&B songs that became part of their sets.

And he was instrumental in creating the early "bad boy" image, with the black leather jackets, an image Epstein would later ditch when he took over as their manager.

Anthony Esmond Sheridan McGinnity was born in Norwich. He showed an aptitude for music at school and headed off to London in his teens.

He played in clubs and landed a job on the BBC TV pop show Oh Boy!; legend has it that he was the first person ever to play electric guitar on television. He established a reputation as a gifted guitarist and a charismatic, but rather erratic and unpredictable, showman.

Mark Lewisohn, one of the foremost experts on the band, notes in The Complete Beatles Chronicle: "The Beatles held Sheridan in high esteem and would often leave the Kaiserkeller (where they had a residency) during their half-hour breaks to nip across to the Top Ten (where Sheridan was based). Naturally it was only a matter of time before they were up on stage jamming."

The Beatles returned to Hamburg for a second stint the following year, 1961. The group, which at that time consisted of John Lennon, Paul McCartney, George Harrison and drummer Pete Best, played their own sets and backed Sheridan at the Top Ten club.

That in turn led to a recording session for Polydor and The Beatles recorded several tracks as Sheridan's backing band along with Ain't She Sweet, with Lennon as lead singer, and the instrumental Lennon-Harrison composition Cry for a Shadow.

When My Bonnie was released as a single in Germany, the band's name was changed to the Beat Brothers.

While the band's careers took off in England, Sheridan remained in Hamburg and would eventually settle in the area permanently. In the mid-1960s he toured and recorded with the Glasgow band The Bobby Patrick Big Six.

In 1967 he went to Vietnam to perform for the troops. His band found themselves caught up in the action. One group member was killed and it was erroneously reported that Sheridan was dead.

Sheridan went on performing and recording, but found it impossible to escape from the shadow of those early recordings with The Beatles, which have been continually repackaged and rereleased.

He was married three times and is survived by five children.