Before Ellen DeGeneres became a groundbreaking comedian earning $75 million a year, she was "completely lost," as she told Tulane University's class of 2009.

"When I finished school ... I had no ambition. I didn't know what I wanted to do. I shucked oysters; I was a hostess; I was a bartender; I was a waitress; I painted houses; I sold vacuum cleaners ... I thought I would finally settle on some job, and make enough money to pay my rent."

But after a personal tragedy, DeGeneres began writing, and she penned a piece that would change her life.

"What poured out of me was an imaginary conversation with God, which was one-sided, and I finished writing it, and I looked at it and said to myself .... I'm going to do this on 'The Tonight Show with Johnny Carson,'" DeGeneres told the Tulane students.

Ask DeGeneres, as author Yael Kohen did in her book " We Killed," and she'll tell you that she "never intended to change anything." Yet by stumbling into stand-up, that's exactly what she did.

Here are five other trailblazing funny women whose humble beginnings led to legendary careers.

Carol Burnett

For Carl Reiner, the man behind genre-defining productions like "The Dick Van Dyke Show," Carol Burnett is "the single most talented performer ever."

But before she earned that title, breaking the sketch comedy mold with her namesake series in the late '60s, Burnett was a hat-check girl.

Born in Texas to parents who struggled with alcoholism, Burnett grew up as a child of modest means with her grandmother in Hollywood. She initially picked journalism as her field when she started at UCLA in 1951, but an acting class soon opened Burnett's mind to new possibilities.

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In 1954, she packed up for New York with her sights set on a career in musical comedy. "I had no plan. I don't know what I thought -- I guess that I would land and all of a sudden there would be the flipping pages of a calendar and then you'd see me on Broadway, like in a movie," Burnett told The Washington Post . Instead, she found herself paying $18 a week to split one boardinghouse room five ways.

Her first few years were spent hustling in search of her big break, but that's where grit came in: "I was never afraid," Burnett recalled of her time entering show business. "I knew in my heart I would make a living so that I could put food on the table, clothes on my back and pay the rent."

Amy Poehler

For Amy Poehler, it was working part-time in a retro ice cream parlor before college that solidified her icy resolve.

When she took the job, Poehler described in an essay for The New Yorker , she wasn't even sure she wanted to be bothered with show business at all.

"I was planning to go to Boston College as an English major and maybe become a teacher, like both of my parents," Poehler said. But the ice cream gig had "a performance element" to it, and Poehler found that when she "stood in the dining room and demanded attention I was reminded of things I already secretly knew about myself. I wasn't shy, I liked to be looked at, and making people laugh released a certain kind of hot lava into my body that made me feel like a queen."

After a summer spent taking sundae orders from teen boys who asked Poehler to "hold their nuts," the future comedy star knew what was before her -- and it didn't include an ice cream scoop or serenading patrons on their birthdays.

"I quit when the summer ended," Poehler recalled in her essay. "I was angry; I wanted to be gone. ... (I) was aching for what came next. I felt my whole life stretched out before me ... I turned toward my future, mouth watering."

Tina Fey

Known today along with Amy Poehler as one of the women who has redefined American comedy, Tina Fey always knew where she wanted to be: in front of an audience, cracking jokes.

"Somewhere around the fifth or seventh grade I figured out that I could ingratiate myself to people by making them laugh," Fey told Believer magazine in 2003. "After a while it became part of my identity. ... I was already trying to define myself as 'the jokester.'"

So when she landed in Chicago in the early '90s, she zeroed in on the iconic Second City, where she could study improv at night. And by day? The future first female head writer of "Saturday Night Live" could be found working the front desk at a local YMCA.

"I had the worst shift imaginable. Five-thirty in the morning 'til 2 in the afternoon," Fey told Believer. "But I had my nights free to take classes at Second City. ... I was very serious about it. I was like one of those athletes trying to get into the Olympics. It was all about blind focus. I was so sure that I was doing exactly what I'd been put on this Earth to do."

Phyllis Diller

Considered today to be the grande dame of comedy, a pioneer who kicked open the door for other women in stand-up, Phyllis Diller's career almost didn't happen.

For roughly the first two decades of her adult life, Diller was a housewife and mom of five kids. She was trained as a classical pianist but didn't work in music; in the early 1950s, right before she got her big break, she worked as a copywriter for the San Leandro News-Leader newspaper in Northern California to help pad her family's income.

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But comedy was always as natural as breathing for Diller. According to the Los Angeles Times , Diller once said that from the age of 12 she found "the only way to handle the terror of social situations was comedy — break the ice, make everybody laugh. I did it to make people feel more relaxed, including myself."

She was so funny that her husband encouraged her to try telling jokes professionally. Her first stand-up set came at San Francisco's Purple Onion Club on March 7, 1955. By the 1960s, Diller's career -- and her trademark blond hair, eccentric outfits and groundbreaking quips about relationships, beauty and womanhood -- was one for the history books.

Whoopi Goldberg

The comedic force who would one day win an Oscar for her supporting role in the 1990 movie "Ghost" (not to mention deliver the quote that launched 1,000 memes) worked among the dead while she was trying to make her way in show business.

It was the mid-'70s, and Goldberg moved from her native New York to California. Since she'd gone to beauty school, Goldberg did have options to support herself, although she might not have anticipated that she'd find work as a mortuary beautician.

"I was a hairdresser on dead people," the award-winning entertainer told Time magazine in 2010 , "which made it clear to me that you can be evicted at anytime. Make the best you can with the time you have."

That Goldberg did: In addition to winning an Oscar, she has also become a member of the limited and coveted EGOT club, having also earned Emmy, Grammy and Tony honors.