How Britney is winning is beyond me
For those who have said Eminem hasn't influenced younger generations: 50 Cent, K. Dot, Tyler the Creator, Hopsin, MGK, Asher Roth, J. Cole, Chance the Rapper, and others have cited him as an influence.
He's garnered respect from the likes of Kool Moe Dee, Jay Z, The Game, Rakim, Redman, Dr. Dre, Nas, Kanye West, Scarface, Kool G. Rap, Snoop Dogg, Lil Wayne, Lupe Fiasco, Tech N9ne, T.I., Obie Trice, Crooked I, Ice-T, Drake, Kurupt... both his contempories and well respected, legends in his own field. People love to say the reason he excels is because of his race when that simply isn't the case. Most rappers do consider him a legend. Many are afraid to even collab with him out of fear of him outshining them on their own song (i.e Renegade).
"Lose Yourself" and the movie 8-Mile were huge and even earned him an Oscar, the first hip-hop artist to ever do so.
A white boy with bleach blonde hair is almost synonymous to Eminem.
The word, "Stan" was coined and popularized by him.
He has a unique style, is very hands on with his work, and is often recognized for it.
He's the main catalyst for rap music transcending the Atlantic and becoming global.
No, he isn't the first white rapper and many people don't even recognize him as such, because he actually is talented.. Of course his race may have gained him some type of privilege, but the guy can stand on his own and has a load of talent to back it up. There were the likes of Vanilla Ice, Marky Mark, and the Beastie Boys, but none were quite like Eminem and I don't think any of them influenced the new wave of "white emcees" like Yelawolf, Action Brunson, Asher Roth, Mack Miller, and MGK
nearly as much as Eminem. To many, Eminem is like the majority of hip-hop artists growing up in a similar lifestyle. He's much more believable and authentic.
I remember when Britney and Em both first hit the scene and they both were massive and controversial. Em, because he had no filter and had everybody up in arms and, Britney, because she was oozing sex appeal at such a young age. They both were phenomenons, but because here we are 15 years later and Eminem is still able to sell out stadiums, push millions of albums (even more so than more current artists sans Adele), and is still a farce to be reckoned with, I would have to say he is the bigger legend.
This isn't taking anything away from Britney because not many have had the peak she had, but Eminem is... an anomaly.
it's undeniably true that vanilla ice (who came after the beastie boys) made it so that white guys rapping were seen as novelty jokes when he first started out. Labels weren't taking him seriously because of that. The surgence of white rappers in recent years has been credited to him, and all white rappers are compared to him, not the beastie boys who were major and helped a lot but were not traditional rappers they were more rock/rap. Eminem got more demographics listening to rap in more countries. It's the truth. Not a 'race card' 
