Almost everyone knows Bob Dylan’s real name is Robert Zimmerman and Mel Brooks’ real name is Melvin Kaminsky.

But did you know Chevy Chase and Michael Caine have been using stage names? It’s true! And we’re willing to bet you didn’t know that.

Here are 10 real names of famous celebrities we bet you didn’t know, as listed by Business Insider (which has a much lengthier list of 30):

10. Reese Witherspoon (Laura Jeanne)

Ten Real Celebrity Names We Bet You Didnt Know

Reese Witherspoon in “Legally blonde” (image source: screen grab)

Famous for her role in the Johnny Cash biopic “Walk the Line” as well as her performance in the romantic comedy “Sweet Home Alabama,” Witherspoon swapped her first and middle name in for “Reese,” her mother’s maiden name.

9. Christopher Walker (Ronald Walken)

Ten Real Celebrity Names We Bet You Didnt Know

Christopher Walken in “The Deer Hunter” (image source screen grab)

As it turns out, Walken was originally named for actor Ronald Coleman

“The change in name came about after singer Monique Van Vooren, whom Walken worked for at the time, renamed him Christopher for no real apparent reason,” Business Insider (BI) notes. “The name stuck, though his friends still call him Ronnie.”

8. Natalie Portman (Natalie Herschlag)

Ten Real Celebrity Names We Bet You Didnt Know

Portman played a key role in ensuring the Star Wars prequels were totally unwatchable (image source: screen grab)

Known best for her performance in three terrible Star Wars movies, the “Garden State” actress was born Natalie Herschlag in Israel in 1981.

Her father is named Avner Hershlag. The family of her American mother, Shelley Stevens, changed their named from “Edelstein” when they came to the United States from Austria and Russia.

The “V for Vendetta” actress currently holds dual American and Israeli citizenship.

7. Jodie Foster (Alicia Christian Foster)

Ten Real Celebrity Names We Bet You Didnt Know

Jodie Foster acts alongside Robert De Niro in Martin Scorsese’s classic “Taxi Driver” (image source: screen grab)

It’s almost impossible to forget Foster for her role as a supposedly easygoing teenage prostitute in Martin Scorsese’s 1976 classic “Taxi Driver.”

But it’s pretty easy to forget Jodie isn’t her real name.

“Foster’s estranged brother Buddy claims her name change to ‘Jodie’ came as the result of a nickname, the code, ‘Jo D’ for their mother’s partner, Josephina Dominguez,” Business Insider notes, citing Buddy Fosters’ book, “Foster Child: A Biography of Jodie Foster.

6. Jamie Foxx (Eric Marlon Bishop)

Ten Real Celebrity Names We Bet You Didnt Know

Jamie Foxx as Ray Charles in the 2004 biopic “Ray” (image source: screen grab)

He made a name for himself with the popular television show “In Living Color” and had his superstar status confirmed by his performance in the 2004 Ray Charles biopic “Ray” – but none of it happened under his actual name.

“Rumor has it Foxx picked an androgynous name because he noticed female comedians were often picked over men to perform at comedy clubs,” Business Insider notes.

5. Ben Kingsley (Krishna Pandit Bhanji)

Ten Real Celebrity Names We Bet You Didnt Know

Ben Kingsley as Mahatma Gandhi (image source: screen grab)

The Oscar-winning actor solidified his place as a Hollywood heavyweight with the 1982 epic “Ghandi.”

But like Foxx and Walken, it wasn’t under his real name.

The noted actor admitted in an “Inside the Actors Studio” interview that he believed his foreign name would hinder his professional career.

4. Michael Caine (Maurice Joseph Micklewhite)

Ten Real Celebrity Names We Bet You Didnt Know

Michael Caine as Lt. Gonville Bromhead in the 1964 classic “Zulu” (image source: screen grab)

From battling Zulus to scamming the wealthy as a dirty, rotten scoundrel to assisting master Bruce Wayne, Michael Caine is easily one of Hollywood’s most famous and beloved actors.

But he didn’t get there by using his birth name.

At the urging of his agent and as a tribute to his hero Humphrey Bogart, the British actor decided early on to take the name Caine, according to IMDB.

“Bogart was my hero, and even though he came from a sort of snobby, aristocratic family—he was a distant relation of Princess Diana—when I was a kid I thought he was a tough guy,” Caine said in New York Magazine interview. “Any person with my working-class background would be a villain or a comic cipher, usually badly played, and with a rotten accent. There weren’t a lot of guys in England for me to look up to.”

3. Chevy Chase (Cornelius Crane Chase)

Ten Real Celebrity Names We Bet You Didnt Know

Chevy Chase in one of his many skits lampooning then-President Gerald Ford (image source: Vanity Fair)

You’re probably familiar with his National Lampoon comedies and his Saturday Night Live routines. But if you’re like most Americans, you probably had no idea Chevy Chase isn’t his real name.

“Cornelius Crane Chase was named after his mother’s adoptive father, Cornelius Vanderbilt Crane, heir to the successful New York company, Crane Plumbing,” Business Insider notes.

“The nickname Chevy was given by his grandmother, from the medieval English ‘The Ballad of Chevy Chase.’ As a descendant of the Scottish Clan Douglas, she felt the name ‘Chevy’ seemed fitting.”

2. Meg Ryan (Margaret Mary Emily Anne Hyra)

Ten Real Celebrity Names We Bet You Didnt Know

Meg Ryan and co-star Tom Hanks in the 1990 comedy “Joe Versus the Volcano” (image source: screen grab)

Did you know that Hollywood’s former rom-com darling has been working all these years under a fake name?

We didn’t.

“Born in Fairfield, Conn., to Roman Catholic parents named Susan Jordan and Harry Hyra, Margaret Mary Emily Anne Hyra changed her name to Meg Ryan after she dropped out of NYU one semester early to pursue her budding acting career,” BI notes.

1. Joaquin Phoenix (Joaquin Rafael Bottom/Leaf Phoenix)

Ten Real Celebrity Names We Bet You Didnt Know

Joaquin Phoenix as the corrupt and murderous Roman emperor Commodus in Ridley Scott’s “Gladiator” (image source: screen grab)

This actor’s decision to change his name — more than any other name change on this list — makes perfect sense.

“Joaquin Rafael Bottom is the third of five children, all with equally interesting names, including River (1970–1993), Rain (1973), Liberty (1976), Summer, and a half-sister Jodean,” BI says. “After Joaquin’s parents, John Lee and Arlyn Bottom, married in 1969, the couple joined the religious cult the Children of God and traveled around South America. But they soon became disenchanted with the cult and moved back to the U.S. in 1978, where they changed their last name to ‘Phoenix’ to symbolize ‘new beginning.’”

But it was Joaquin when he was younger who wanted to be called “Leaf,” perhaps in an attempt to identify with his siblings’ nature-related names.

“In a past Jay Leno interview, Joaquin said he had originally called himself ‘Antleaf’ as a child,” BI adds. “Leaf would become the name he would use as a child actor until, at age 15, he changed it back to Joaquin.”

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