In the 90s, the Backstreet Boys were on top of the world. They sold over 100 million records across the globe, had hearts throbbing in every country, and were the type of boy band that would span decades.

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But no matter how much you loved BSB when they first became famous, there are probably some things you don't know about them. After all, the guys tended to keep their private lives private while performing as the Backstreet Boys, even when some of the members were having personal issues. From legal strife to falling outs between group members, here are 10 things most fans don't know about BSB.

20 AJ McLean Was The First Member

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While some boy bands get started because the members are friends first, that wasn't the case with BSB. In fact, all the guys responded to casting calls from Lou Pearlman, the now-disgraced (and deceased) former manager of NSYNC, Backstreet Boys, and numerous other boy bands.

AJ McLean was the first to sign up with BSB, after auditioning for his role. The other four guys — Kevin Richardson, Nick Carter, Brian Littrell, and Howie Dorough — came after. Unfortunately, though Ryan Gosling could have been a member, he opted out.

18 The Band Was Big In Europe First

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When the Backstreet Boys first got together, they weren't huge in the U.S. Wikipedia notes that their first concert was at SeaWorld Orlando, with a handful of other small gigs to follow. What really spurred them to fame was the success of their first song in Europe.

"We've Got It Goin' On" wasn't huge in the U.S., despite what 90s kids later thought, but it did top charts in Europe. Later, NSYNC would follow this same model of success under Lou Pearlman's guidance.

16 Brian Littrell Had Heart Surgery On Tour

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Most fans never heard about Brian Littrell's heart issues, at least not until many years after his open-heart surgeries. In 2008, ABC News reported that Brian's son Baylee has Kawasaki syndrome, a condition that involves swollen blood vessels.

Brian himself was born with heart problems. At age five, he had surgery to correct a heart murmur. Then, mid-tour with BSB in 1998, he had a second surgery to repair a hole in his heart. Unfortunately, heart problems might be hereditary in the Littrell family.

14 Orlando, FL Had An Official BSB Day

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BSB may not have reached the level of 90s meme fame that Justin Timberlake's hair did, but the mayor of Orlando, Florida, did give the Backstreet Boys the key to the city. He also declared the day Backstreet Boys Day, something that would have delighted fans had they known about it at the time.

October 7th was the official BSB day, noted Orlando Sentinel, and it was a result of the boys raising money for tornado relief in the Orlando area. The headlining act was responsible for contributing over $250K to the cause.

12 Nick Spurred The Band's First Hiatus

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Remember when Nick's little brother Aaron became famous? While things later went downhill for Aaron Carter, it seemed that Nick also wanted his chance at a solo career. At one point, Nick left the band, leaving the other four members to flounder a bit without him.

At the same time, JIVE records apparently promoted Nick's album to the detriment of BSB as a whole. That meant the guys would go to court (again) with a lawsuit trying to recoup their losses.

10 AJ McLean's Oprah Appearance Got The Guys Back Together

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Shortly after Nick's attempt at a solo run, AJ McLean went on Oprah and talked about his personal struggles. The group was on a hiatus at the time, but they showed up to support their friend and bandmate.

After that, the guys started spending more time together, both in and outside the studio. By 2004, they were working on a new album together, plus touring around Asia, then Mexico. But after another successful album, Kevin Richardson jumped ship and threw another wrench in the BSB works.

8 NSYNC Almost Merged With BSB

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When Kevin Richardson left the group, which did make headlines, some other things happened behind the scenes. Did fans realize that the two biggest competitors in the boy band world nearly merged?

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In 2006, when Kevin left the group, there was buzz about what would happen next. After all, it was tough to have a great vocal group without the range of the five members. But the guys didn't want to sub Lance Bass or Joey Fatone for Kevin, so they left it at four for the time being.

6 The Guys Never Wanted To Be A Boy Band

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Sampling songs from BSB's newer albums, including their 2019 release of DNA, show how much range the guys have. Their earlier music was more pop music that fans could dance to, while the newer albums show off their vocal abilities much better.

But the truth was, the members of BSB never wanted to be a boy band. In one interview, Brian Littrell explained that they wanted to be more like Boyz II Men. But former manager Lou Pearlman wanted to pit them against NSYNC in the battle of the boy bands.

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Just like NSYNC, BSB got fed up with their former manager, Lou. The subject of a 20/20 documentary, Lou Pearlman filed for bankruptcy after scamming investors out of millions of dollars. While he passed away while incarcerated, that didn't help the guys salvage their income, leading them to other BSB-branded pursuits.

RELATED: 10 Things Most Fans Don’t Know About NSYNC

Brian led the group in filing their original lawsuit, and NSYNC also cut ties with Lou after they realized how paltry their paychecks were in contrast with Lou's immense wealth. Despite what fans saw, BSB wasn't raking in the dough - only Lou Pearlman was.

2 Backstreet Never Got All Their Dues

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Because Lou Pearlman passed away before the lawsuits were settled, a handful of talent never got their final payments. BSB's lawsuit, for one, was worth millions, which the 20/20 special revealed Lou had hidden away somewhere.

Instead, Lou passed away behind bars, and the Backstreet Boys, among other acts he'd wronged, were left to create their own future. Fortunately, they're a creative bunch, and definitely don't need a shady manager to make great music (or avoid becoming one of many forgotten 90s stars).

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