The Harlem Globetrotters are trotting through Canada right now and performing two shows in Calgary this week.

And they need no introduction.

Harlem Globetrotters

Dizzy Grant is one of the stars of the Harlem Globetrotters. (harlemglobetrotters.com)

We all know they spin basketballs on their fingers, but they also have a long history that's full of a few surprises.

They've been around for a while

According to the Globetrotters website, the team is celebrating its 90th anniversary this year.

But sport historians have never been able to agree on the exact date they played their first game.

Brian Green, authour of Spinning the Globe: The Rise, Fall, and Return to Greatness of the Harlem Globetrotters says one thing that is for sure — this iconic brand got its start in Chicago in the 1920s.

Best team in the world

Green says back in the 1940s and 1950s, the Globetrotters regularly crushed the "best white teams" in the NBA.

That's because they had a "monopoly" on the best black basketball players who were not allowed to play in the professional league until 1950.

"In fact that's, I think one of the main reason the NBA integrated was the Globetrotters beat their champions two years in a row — the Minneapolis Lakers," said Green.

Making NBA history

It was a Globetrotter who opened the doors for African-American men in the NBA.

In 1950, Chuck Cooper became the first black player to sign a contract with the league.

And that, says Green, is when the Harlem Globetrotters started to go "downhill."

"The best players were going to the NBA," he said.

Almost went bankrupt

Green says it was after the NBA started drafting all the best black players that the Harlem Globetrotters started getting away from real basketball.

"[They] became a clown act."

He says by the '90s they were "on the verge of bankruptcy."

It was a former player who turned things around.

Mannie Jackson bought the team in 1992 and started replacing older members with younger ones.

"He got 'em back to their roots which was you could have great basketball players but you could also have the funny stuff too," said Green.

Loss against The Washington Generals

Very few teams have beaten the Harlem Globetrotters, and when they did, it was always a big deal.

But it was their 1971 loss in Martin, Tennessee, that was a real shocker to fans.

They were beaten by the Washington Generals, who were formed to play exhibition games against the Globetrotters when they were on tour. For more than 40 years, the Generals only won once (but the Generals will tell you it was twice).

In his book, Green quoted the Generals' founder Louis Klotz

"Beating the Globetrotters," he once said, "is like shooting Santa Claus."