Eminem's long time manager Paul Rosenberg has been named the new head of Def Jam.

He will replace CEO Steve Bartels, who's led the Universal Music Group imprint since 2013.

Bartles is expected to stay on until the end of the year.

Def Jam was founded in 1983 by Rick Rubin and Russell Simmons. Their artists have included LL Cool J, Beastie Boys, Justin Bieber, Nas, Rihanna and Kanye West.

[Related: YG furious at Def Jam after mixtape leaks.]

Rosenberg, 46, will also continue to manage Eminem.

"He’s super smart and will steer the company in the right direction," a source told Variety about Rosenberg's hiring.