The 36-year-old actress, whose engagement to Prince Harry just became public, graduated from Northwestern University School of Communication in 2003, after she turned 21.
But during the years before, when she was under the legal drinking age, she pulled some sneaky moves that make her a perfect match for Britain's party-loving royal, a source claims.
Californian Markle was known by her real name, Rachel Markle, back in the early 2000s when she attended Northwestern, where she double-majored in theatre and international relations.
She was a fresh-faced ambitious young woman who already had her sights set on making it in Hollywood, and would often sneak off for secret auditions for TV commercials.
But she still found time to let her hair down in the Windy City, in between studies at the prestigious acting establishment that's also shaped the careers of David Schwimmer, Warren Beatty, Stephen Colbert, Julia Louis-Dreyfus and Zach Braff, to name a few.
One former student claimed to to RadarOnline.com: "Meghan had a fake ID during her time at university and told us about it when she visited the campus in 2014. She said she used it to drink at The Keg, which was a popular student bar for years, and she also got a job at a club in the city."
"You can get two fake IDs for about $100 in Chicago, it's a bit sketchy and not everyone has one," said the former student. "She seems like the perfect modern princess now, but she lived university life like most teenagers and was really popular on campus. Everyone talks about her going here."
The Keg of Evanston later lost its liquor license after management had a tumultuous time wrangling with city officials over underage drinking. "It was a sh** hole, full of underage girls drinking and crazy boys starting fights," former general manager Chris Nora claimed to RadarOnline.com.
When she wasn't studying, auditioning for roles, or partying in bars, she was down at the local Burger King, which caused her to pile on weight in her first year of university.
In an interview with the North by Northwestern during her 2014 return, Markle said: "It's surreal being back because I haven't been back since I graduated and as I am walking around I remember things like the schlep of getting to South Campus from up north. The 24-hour Burger King also definitely helped me put on the Freshman Fifteen."
Markle also spent plenty of time with her sorority crowd, Kappa Kappa Gamma, but instead of focusing on sisterhood, it has been criticized on greekrank.com in countless negative comments over the years.
Despite the bad reviews, student Melania Hidalgo, a member of talked-about KKG, defended the sorority, insisting members, like Markle, are hard-working women who aspire to do well in life. "We're intelligent hot messes. The thing we all have in common is we're all very driven, ambitious, and passionate," said Hidalgo. "Meghan was the recruitment chair of the sorority during her time here. She was in charge of bringing in new girls, you have to be a very friendly and outgoing person."
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