The beef had began in 1997 when Eminem was first releasing his Slim Shady EP he was throwing a record party and had been handing out flyers to random people he saw Violent J of ICP and handed him a flyer. According to Violent J, it read: "Special appearances: ICP (maybe), Esham (maybe)".
Violent J got upset and asked Eminem why he didn't first consult them before putting them on the flyer. Eminem replied, "I said maybe. Maybe you'll be there, maybe not. I'm asking you now" Violent J then replied "fuck no you should have asked us before putting us on this motherfucking flyer man, so hell no we ain't coming" and then Violent J walked away.
during interviews and in his freestyles, such as "Till Hell Freezes Over", where he raps Fuck "ICP, Buy My CD!", and Drastic Measures. This lead fans to hate them for their false identities.
ICP then made a remix of Eminem's hit song "My Name Is" entitled "Slim Anus" (Twiztid doing the vocals mostly) and another song entitled "Shittalkaz" (2000).
In the middle of one of Em's concerts, his phone rang. He answered it, and heard a voice say: "Hi, this is Violent J from ICP. Can I suck your dick?"
Eminem also responded to this remark on The Marshal Mathers LP with a song titled "Marshall Mathers", which completely killed the song "Slim Anus". Following the song was a skit entitled "Ken Kaniff", where Violent J and Shaggy 2 Dope are giving Ken a blowjob.
Eminem also dissed ICP throughout D12's debut album Devil's Night and got into trouble when he pulled a gun on ICP's road manager Douglas Dail later that year. In addition, Eminem dissed ICP again in a concert during the Up in Smoke Tour, where he brought out 2 blowup dolls with ICP face paint. ICP responded to this incident a few times in later 2000, with the songs: "Please Don't Hate Me", "Cherry Pie", and "My Homie Baby Momma".
"Please Don't Hate Me" is about Violent J calling Eminem and admitting to sexual intercourse with his mother, while "Cherry pie" only had a single line spat from Violent J insulting Eminem's mom. "My Homie Baby Momma" was about Shaggy 2 Dope trying to convince Eminem's wife at the time, Kim Mathers, to have sex with him. Eminem can be heard 3 times in the song (imitated by Twiztid).
In 2001, ICP made a major dis to Eminem titled "Nuttin' But a Bitch Thang". Later at a Juggalo gathering, they used a blowup doll of Eminem to act out a similar skit of what Eminem did in 2000.
Eminem made a few comebacks in 2002 with his song "Business". He also made jabs at the group with the song "Monkey See, Monkey Do" on his 2003 EP Straight from the Lab.
Later in 2003, ICP's Shaggy 2 dope insulted Eminem's wife in the song "Hard Times" by Esham.
The feud ended in 2005 when Proof and the rest of D12 played a bowling game with ICP, even though Eminem wasn't there at the time.
In 2009 Eminem made a track called "Chemical Imbalance" referencing ICP. ICP stated that they liked Eminem's 2009 album Relapse, and later in 2013, Eminem made 3 shout-outs to ICP stating that he liked their song "Miracles", and in 2017, ICP made an appearance on Shade 45.