WWE knows one thing or certain — controversy sells. From the early days of the company, they worked angles that they knew would send fans into a frenzy. Even when Bruno Sammartino was champion, WWE knew that they could sell more tickets when fans wanted to see an evil communist like Ivan Koloff get beaten. When it was time to build Hulkamania, they put the title on Iron Sheik to lose.

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However, there are also times where controversy can become dangerous. Stories in the old days were scary, like the time WWE had to sneak Ivan Koloff out of the arena after he beat Bruno for the world title. With that said, fans bought tickers in droves to see these controversial characters, and that is what made WWE the biggest company in the world during the Attitude Era. With that in mind, here are the 10 most controversial characters in WWE history.

10 SGT. SLAUGHTER

In 1990, any person would think that WWE fans would know that the entire industry is scripted, and the wrestlers are all portraying characters. However, in that year, fans reacted to a fictional storyline like it was real life. A lot of that had to do with the Gulf War in Iraq.

Sgt. Slaughter turned heel against Hulk Hogan, but he also turned heel against America to become an Iraqui sympathizer. He even took on an Iraqi manager! Even worse, WWE wanted him to burn the American flag for heat. Sarge drew the line there, burning a Hulkamania shirt instead. Regardless, Slaughter said he and his family received death threats due to his controversial character.

9 MUHAMMAD HASSAN

Muhammad Hassan was the biggest missed opportunity in WWE. His original character was brilliant. Hassan was an American-born man who claimed that he faced daily discrimination because people believed him to be a Muslim, and therefore a terrorist. This was after 9/11, and the entire angle was brilliant.

Everything Hassan said was true, and that made him even more hated because he was right. However, WWE couldn't resist an evil foreigner angle and turned Hassan from someone who preached against discrimination into a terrorist with henchmen who attacked Undertaker. The networks understandably freaked out and ordered WWE to remove Hassan from television, destroying the young man's career.

8 THE MEXICOOLS

WWE has always struggled with foreign-born superstars. While they are better now than before, they at one time couldn't bring in foreign wrestlers without making them a caricature of their nationalities. This was proven with the Mexicools.

Juventud Guerrera was one of the best cruiserweight wrestlers in the world at that time. Super Crazy proved in ECW that he was one of the most daring and exciting wrestlers in the sport. Psicosis was a great athlete. So, to honor these amazing credentials, the WWE had them come to the ring on lawnmowers, dressed as laborers — a blatant and insulting mockery of Mexicans in America.

7 EUGENE

Nick Dinsmore broke into the sport WWE's developmental program in Ohio (OVW) and was a quick success. He won the tag team titles with Rob Conway, and the team held the tag titles ten times, the most in history. He then won the OVW singles title a record 10 times as well.

With such great success in OVW, it seemed he was primed for something special in WWE. He got more than he bargained for when WWE brought him up as Eugene, the "special" nephew of Eric Bischoff. Eugene was a parody of a mentally disabled man who just tried to mimic the moves of his favorite wrestlers. Let's just say it's a gimmick that won't fly today.

6 ROWDY RODDY PIPER

The most controversial WWE superstar of the '80s was none other than Rowdy Roddy Piper. Yes, he soon became one of the most beloved wrestlers in WWE history, but at one time he was the most hated man in the sport. The biggest reason fans hated him was because of his mouth, as he was the best heel promo in the game.

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He also crossed the line many times. He smashed a coconut over Jimmy Snuka's head, insulting his heritage. He destroyed a jobber that he had on his show. He feuded with the most popular wrestler in the world in Hulk Hogan. Even as a babyface, he was controversial with a perfect example of painting half his body black to battle Bad New Allen.

5 ANDRE THE GIANT

Andre the Giant was the most popular man in wrestling history. He was the undefeated and lovable giant, a man who fought for what was right. Andre went from territory to territory in the 70s and 80s, beating the biggest heels in the world. In WWE, he was slowing down but was still a massively popular babyface.

Then, Andre learned that Hulk Hogan would never agree to put his title on the line in a match with the Giant. Andre turned heel for the first time, a shocking move, and he hired Bobby Heenan. He ended up beating Hogan for the title and in the most controversial move of his career, sold the title to The Million Dollar Man.

4 BROCK LESNAR

Brock Lesnar is one of the most controversial wrestlers in WWE today for a very different reason. This controversy has nothing to do with an angle, turning on a wrestler, or doing something dastardly in the ring. No, Lesnar is controversial because he openly makes it clear he is only in this for the money.

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Brock Lesnar has no love for professional wrestling. That is not to say he is not a brilliant mind, as he knows what he needs to do to sell a match and knows what fans will pay for. However, Brock holds world titles for a long time and hardly ever shows up. To date, he has had one televised, non-PPV match in the last decade.

3 KAI EN TAI

As mentioned with The Mexicools, WWE has no idea how to treat foreign-born stars properly. They are doing better now, as seen with names like Andrade Cien Almas and Shinsuke Nakamura, but in the past — and specifically the Attitude Era — things were bad.

Kai En Tai had some fantastic Japanese superstars in the faction, from TAKA Michinoku and Sho Funaki to Dick Togo. However, WWE turned them into jokes. They dubbed in a deep voice saying "EVIL" to play over TAKA and Funaki talking. Don't even start thinking about their "choppy choppy" angle with Val Venis!

2 THE GODFATHER

Charles Wright went through a lot of gimmicks before he finally found one where he could be himself. He was Papa Shango, a voodoo priest who was able to use magic to hurt Undertaker. He was Kama Mustafa, an MMA fighter in an era where MMA wasn't big-time yet. However, in 1998, he got a chance to be himself.

However, he was controversial in all the best ways for the Attitude Era. He was The Godfather, a pimp. Godfather would come to the ring with his "Ho Train," which usually consisted of exotic dancers found at local clubs. This gimmick would bomb hardcore today, but for the Attitude Era, controversy sold, and Godfather became a WWE Hall of Fame star.

1 MR. MCMAHON

Mr. McMahon might be the most controversial character in WWE history. He started as the owner of the company and built it into what it is today, while only serving as a commentator and staying out of the spotlight otherwise. However, after McMahon screwed over Bret Hart at the Montreal Screwjob, he became an on-screen character.

Since then, McMahon has been the evil boss, tormenting Stone Cold Steve Austin. He was the Higher Power, sacrificing his daughter. He was involved in angles cheating on his wife with Trish Stratus and Sable. He mocked religion when he fought "God" in a wrestling match. Controversy sells, and Mr. McMahon is the true definition of controversy in WWE.

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