Simon & Garfunkel were one of the most successful singer-songwriter duos in history.

But behind the scenes, the men, whose friendship stretched back to their childhood days, were constantly at each other's throats. Considering the beautiful harmonies they made together, it's hard for many fans to comprehend just how disharmonious Simon & Garfunkel's relationship was.

The duo originally found success under the name Tom & Jerry, scoring a minor hit with their 1957 single "Hey Schoolgirl.” Around this time, Paul Simon was offered the chance to record some solo material - an offer he accepted without discussing it with his musical partner, Art Garfunkel, who later said that Simon’s decision left their friendship “shattered for life.”

After Tom & Jerry ended, the artists went their separate ways, only to reconnect in 1963. By 1965, music fans began to take notice. The hits came quickly over the next few years, including “The Sound of Silence,” “A Hazy Shade of Winter,” “Scarborough Fair,” “The Boxer,” “Mrs. Robinson” and “Bridge Over Troubled Water.”

With heightened popularity, it was Garfunkel now who got an offer outside the duo, given the chance to pursue an acting career. When Garfunkel accepted a role in the 1971 film Carnal Knowledge over working on a new album, Simon was furious. “He knew how I’d feel, but he did it anyway,” Simon declared in his biography. “I thought, ‘Fuck you, I’m not going to do that.’ And the truth is, I think if Artie had become a big movie star he would have left. Instead of just being the guy who sang Paul Simon songs, he could be Art Garfunkel, a big star all by himself.”

Looking at the tumultuous Simon & Garfunkel relationship, jealousy is a common theme. Associates observed that Simon was jealous that his counterpart garnered much of the attention and spotlight as the duo’s main singer. Garfunkel, meanwhile, was reportedly envious of his partner’s songwriting.

The result has been an on-again, off-again relationship that has left both men stubbornly frustrated for years. The duo's history is filled with reunions, breakups, arguments, cheap shots and even an uncomfortable exchange onstage at the Rock & Roll Hall of Fame.

Learn more about the feud between Simon & Garfunkel in the video below.

Paul Simon / Simon and Garfunkel Albums Ranked

Paul Simon was always an uneasy folksinger, a role his record company tried to push him into starting with Simon & Garfunkel's debut album.