People have been genuinely surprised after recently learning about Charlie Sheen's real name and ethnicity.

Sheen, who has received numerous accolades including a Golden Globe Award and nominations for four Primetime Emmy Awards and three Screen Actors Guild Awards, is best known for his roles in award-winning TV series and blockbuster films, including Two and a Half Men, Platoon, Ferris Bueller's Day Off, and the Scary Movie franchise.

The 60-year-old has also been in the news for decades due to incidents involving substance abuse, as well as relationship and legal challenges.

In a new documentary, Sheen, who has been sober for seven years, openly discussed his rise to fame and subsequent public challenges, joined by family and friends who revealed untold stories of 'his journey through stardom, struggles, and redemption'. As a result, many Netflix viewers are just now realizing what his real name is following the documentary's release earlier this month (10 September).

Sheen's birth name is quite different from the name we know him by.

Seriously, how do you go from 'Carlos Irwin Estévez' to 'Charlie Sheen'?

Well, for those unaware, Sheen is the eldest son of Hollywood A-lister Michael Sheen (born Ramón Estevez) - famous for roles in cult classics like Apocalypse Now, The Departed, and Wall Street, so the last name makes sense, but why change the first name?

"I really liked the way it looked," Sheen wrote in his new memoir, The Book of Sheen.

"I’d sat with Pop the week earlier and got his blessing for the name swap. It was a much smoother father-son, Estevez-to-Sheen transition than the one Dad had with his own father. I told him how important it was to honor him by carrying the name forward."

Charlie Sheen's birth name is actually Carlos Irwin Estévez (Netflix)

After making this discovery, fans rushed to social media to express their astonishment, with one X user writing: "Still blows my mind that Charlie Sheen’s real name is Carlos Estévez and his brother is Emilio…"

"It's crazy because yesterday I found out that his real name is Carlos Estevez (Charlie Sheen is his stage name)," quipped another.

A third added: "Charlie Sheen’s real name is Carlos Irwin Estévez [mind blown emoji]."

"Lol I’m watching his documentary on Netflix and his real name is Carlos Estevez. I never knew that!" exclaimed another.

And another X user echoed: "Finding out Charlie Sheen was born Carlos Estevez has completely blown my mind!"

According to ethnicelebs.com, Sheen has Galician Spanish heritage through his paternal grandfather, as well as Irish, English, Scottish, and 'possibly other' ancestry.