An important piece of the Beatles' history is headed for the auction block.

ABC News Radio reports that on Sept. 19, Heritage Auctions will sell off a block of Beatles memorabilia that includes the group's first recording contract. Signed in 1961, it led to the session that produced their German-market cover of "My Bonnie Lies Over the Ocean" — which, in turn, led to the band's career-making partnership with manager Brian Epstein.

"This is perhaps the most historically important Beatles document to ever appear at an auction," argues Heritage's Dean Harmeyer. "Without this contract, which directly led to their involvement with Brian Epstein, the Beatles may have never been able achieve their later success as a recording group. And at the time it was a momentous career milestone — they'd finally secured an actual recording deal, something they had only dreamed of before 'My Bonnie.'"

As unknowns, the members of the Beatles — including drummer Pete Best, who'd yet to be replaced by Ringo Starr — didn't exactly get rich on the recording, which was issued by the German branch of the Polydor label in late 1961; according to the Heritage site, they "were paid what amounted to about $20 each." The contract is expected to fetch roughly $150,000 at auction.

It's being sold as part of the much longer list of items that make up the Uwe Blaschke Beatles Collection, a career-spanning stockpile being sold off by the estate of the German graphic designer who "amassed one of the finest collections of Beatles material in Europe, if not the world, much of which was displayed at a dedicated Beatles museum in Hamburg, Germany." Other items include a signed copy of "Love Me Do" and a photo of a 17-year-old George Harrison.

Author and Beatles expert Ulf Krüger, who helped Blaschke open the museum, tells Heritage that "This collection opens a window to a part of Beatles history that's not well known internationally. John Lennon himself famously said he was born in Liverpool but grew up in Hamburg and this collection documents that transition. There's really nothing comparable to it in the entire world."

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