Eminem is the highest-selling rapper of all time, and this 12-minute freestyle put him on the map in NYC and was a key moment in him getting his big break.

Thursday, August 20, 1998 was only two days after Eminem made his NYC debut at The Tunnel. This was before the days of social media as we know it, so even as talented as Eminem was, there was no such thing as overnight success.

As a matter of fact, he wasn't even known on a national level yet, barely even having a record deal, when he had the opportunity to get on The Stretch Armstrong Show hosted by Bobbito The Barber—a legendary show that was arguably a rite of passage for aspiring MCs by that time.

This was a huge look for Em. Sure, by the summer of ’98 Marshall Mathers’ career was a rapidly growing snowball that was gaining velocity with each passing day, but success was still far from a foregone conclusion. In the previous nine months he’d released the Slim Shady EP regionally, signed to Dr. Dre’s Interscope-distributed Aftermath Records, and recorded his debut LP (though it wouldn’t be released until January of the next year). Those of us close to Em, who had heard the music, knew he had something incredibly special, but to the rest of the world there was still a litany of question marks around the project.

Based in a small college radio studio in NYC, the show ran from 1 a.m. to 5 a.m. and just about everyone from Biggie to Jay Z and Nas made their mark on the program.

There is a movie coming out about the show, and one of the trailers actually features video footage of the iconic 12-minute freestyle that Eminem—who at the time, was a dark-haired hoodie wearing Detroit rapper sans all the millions and commercial success—laid down live over the airwaves in NYC.

(If you're really interested, there is a somewhat lengthy, but insanely detailed account of all the events that took place on that historic night on 114th street in New York here.)

Since then, Eminem has gone on to dominate the charts and become a legendary artist who many still feel owns the crown when it comes to the best MCs on the planet.

Listen to the entire freestyle featuring fellow Detroit rapper Royce Da 5'9" below.

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