Some musical nicknames are pretty easy to figure out — if you wear dark clothes, it’s not unreasonable to be referred to as “The Man in Black.” As for Francis Albert Sinatra, “Ol’ Blue Eyes” made sense, sure, and we can even understand “The Voice” (he was known somewhat for his singing, right?), but what’s up with that corporate moniker?

In his early years, Sinatra was signed to Columbia Records, where he’d released such hits as “I’ve Got a Crush on You” and “Night and Day.” In 1950, sing-along guru Mitch Miller was hired as the head of A&R (Artists and Repertoire) at Columbia, and he arranged for Sinatra to record a series of novelty-type, throwaway songs. A disgruntled Sinatra left Columbia in 1953 and signed with Capitol Records. Frank had some success at Capitol, but still felt frustrated, so in 1960, he formed his own record label, Reprise Records. He released records on his Reprise label, even though he was still under contract at Capitol, which led to a glut of Sinatra product from competing companies for a short while. But Reprise also provided a home for some of Frank’s buddies, such as Sammy Davis, Jr., and Dean Martin.

Sinatra sold Reprise to the Warner Brothers in 1963, but the name his pals had bestowed up him while he was still their “boss” at Reprise stuck forever: The Chairman of the Board.