Little-Known Facts About The Man Behind The Voice Of Optimus Prime

Even if you've never seen a picture of what he looks like in real life, odds are you've heard Peter Cullen's voice at least once in a movie or TV show. That's because Cullen has been one of the leading voice-over artists working in Hollywood for more than 50 years, and throughout his career, he's voiced some of the best-known characters in pop culture, including Optimus Prime from "Transformers."

Cullen began voicing Optimus Prime in 1984 on the original animated "Transformers" series, and he continued throughout numerous TV series for years. When Michael Bay brought "Transformers" to the silver screen in live-action, Cullen was back on board, lending his unique voice to the same character he helped initially bring to life, and fans were incredibly happy to find that nobody replaced him in the role.

Throughout his decades of work in the industry, it's amazing how little people know about the man behind the voice. He's worked on projects most of his "Transformers" fans likely don't know about, so there are more than a few little-known facts about the man behind the voice of Optimus Prime for fans to dive into. Even if you never enjoyed "Transformers," odds are that Cullen's voice came your way at one time or another — and he's lived a fascinating life as well.

Peter Cullen's voice permeates popular culture, but he didn't start out in the field ... at least, not the one you're thinking of. Cullen was born in Montreal, Quebec, where he grew up on a farm. During an interview with NPR in 2014, Cullen told a story about how he found his way to having such a commanding voice: "I had a full dairy barn where I would collect milk pails with my brother, Larry," he recalled. "I found one day that I made a loud noise and all the cows looked up to me ... And I walked down the center of that aisle with these cows looking at me and I said, 'This is fantastic.' I must have been eight years old ... and I was the king of the cows."

Granted, at the tender age of eight, it's unlikely Cullen plotted out the path his life would take. Cullen eventually enrolled at the National Theatre School of Canada, graduating with the school's first class in 1963. After graduating, he began working in radio and soon spread his interests to television, as opportunities kept presenting themselves and helped Cullen establish his career.

While he's known these days for his impressive vocal skills, Peter Cullen didn't begin his career inside a recording booth. He started working in radio in the late '60s, appearing on "Funny You Should Say That" on CBC Radio. He soon transitioned into on-camera acting, appearing in the 1969 children's show "The Buddies," while continuing to work as a radio announcer on nights and weekends.

Through this work, Cullen got his foot in the door for on-camera acting while continuing to hone his vocal abilities on the radio. He appeared in several TV series, off and on, through the end of the 1960s and well into the '70s. Some of his notable credits during this period include appearances on "Comedy Café," "Zut!," and playing multiple characters on "The Sonny and Cher Comedy Hour."

As he continued landing gig after gig, Cullen found roles in more popular series. He spent a couple of years working as the announcer for "The Smothers Brothers Comedy Hour," and he landed similar gigs with "The Bobbie Gentry Show" and other comedy series. This work opened the door to voicing characters, and before long, that became Cullen's primary job.

While you probably know Peter Cullen's voice best through his work with "Transformers," that's hardly the only voice acting role he's had over the years. In fact, Cullen's voice has brought a plethora of popular characters to life on screens large and small for nearly six decades. 

Throughout his career, Cullen voiced numerous characters on "Spider-Man," "Scooby-Doo and Scrappy-Doo," "G.I. Joe: A Real American Hero," and many more. In addition to his animated work, Cullen has stepped into recording booths to voice some surprising live-action characters, including the Mogwai and Gremlins in "Gremlins." He also provided vocalizations (and roars) for the 1976 remake of "King Kong," though he was initially uncredited.

One of the most surprising characters that Cullen voiced is the title monster in "Predator." Uncredited in the role, he gave the Predator a distinctive voice in the form of clicking sounds, and few knew it came from the same throat that brought Optimus Prime to life. Cullen reprised his role in the "Alien vs. Predator: Evolution" video game, voicing three different types of Predators and sounding just as he did in the 1987 feature film.

In the 50-plus years that Peter Cullen has been doing voice work, the one job that most people may be surprised to learn about is Eeyore. Yes, Eeyore, the delightfully depressed donkey from "The New Adventures of Winnie the Pooh," was voiced by the same guy who made the Predator's signature sound. Cullen first began voicing the character on the aforementioned series, which he did for 31 episodes from 1988 to 1991.

Disney wasn't ready to replace Cullen when the next "Pooh" project came along because he continued voicing Eeyore for decades. Cullen voiced Eeyore in 42 separate productions over a period of 29 years. Most recently, Cullen returned to voice Eeyore in a single episode of "Doc McStuffins," but he's also reprised the role in various films as well, including "Pooh's Heffalump Movie" and others.

Not to be limited to those two forms of media, Cullen has also voiced Eeyore in the 2003 video game "Piglet's Big Game" and named the character as his second favorite to voice in a Collider interview. "I loved the characters that were easiest to do," he explained, "that didn't require a lot of screaming and yelling, and stuff like that, because screaming and yelling, it's hard work. But my favorite, outside of Prime, was Eeyore."

Peter Cullen began voicing Optimus Prime in 1984 with the first episode of "The Transformers," and he explained to Collider how he based Prime's voice on his brother, Larry, a former U.S. Marine Corps captain who served in Vietnam.

Cullen told his brother he was auditioning for a "hero truck" but didn't have more information. His brother told him, "Peter, if you're gonna be a hero, be a real hero. Don't be one of those Hollywood pretenders; don't go yelling and screaming and pretending you're a tough guy. Be strong enough to be gentle." That stuck with him, so when he got to the audition, his brother's words lingered in his ear.

He got there and mimicked his brother's voice, saying, "My name is Optimus Prime from the planet Cybertron, leader of the Autobots." He then drove home to tell his brother how the audition went and told him, "Larry, it really went well, and I thank you ... I just impersonated you." Three weeks later, Cullen landed the job that would define his professional career for the next four decades.

Peter Cullen couldn't have known how popular "The Transformers" or Optimus Prime would become when he booked that first gig. After all, children's cartoons don't often have the kind of staying power as "The Transformers" — just look at the lack of live-action "GoBots" movies out there (of course, it should be noted that Cullen also voiced several "GoBots" characters).

Still, it was "The Transformers" that has reigned supreme as an intellectual property unlike its peers, and Cullen has voiced Optimus Prime for decades in television series, video games, and movies. In the beginning, he voiced Prime in the original cartoon series, "The Transformers: The Movie," and other animated shows released throughout the 1980s. But after the first cartoon ended in 1987, there weren't any new "Transformers" properties for Cullen to voice for 20 years. Then, to many fans' surprise and joy, Cullen returned for Michael Bay's 2007 live-action "Transformers" film, continuing to voice the character in numerous video games and every live-action "Transformers" movie produced since then. 

All told, as of 2023's "Transformers: Rise of the Beasts," Cullen has voiced Optimus Prime in 31 different productions, including 13 video games, six live-action movies, and 12 TV series.

Peter Cullen and Optimus Prime go together like James Earl Jones and Darth Vader, but while Cullen has lent his vocal talents to 31 different productions, he hasn't voiced the character in every "Transformers" property. While he continues to voice Prime in the live-action film franchise, Cullen no longer performs the character on television.

This is because Hasbro opted to hire only non-union workers when it developed "Transformers: Cyberverse." Once Cullen was out, they brought Jake Foushee in to play Prime, and he has continued voicing the character in "Transformers: Rescue Bots Academy," the "Transformers: Battlegrounds" video game, and "Transformers: War for Cybertron Trilogy" on Netflix. 

Cullen discussed being replaced during a convention appearance in 2020, comparing being replaced to "grand theft" and specifically calling out Netflix for not hiring union workers. After mentioning that someone else would continue to play Prime and that it hurt him to have that happen, the audience collectively booed, sympathizing with Cullen. He also gave an example of being called in for the "Bumblebee" movie after the film initially hired another actor, with Cullen having to impersonate the previous actor to match the character's mouth movements onscreen.

It's undeniable that "The Transformers" has had an impact on popular culture that's lasted long past its initial comic book and television series. Since then, "The Transformers" have come to dominate multiple areas of pop culture, including a feature film franchise that's raked in over $2 billion in global ticket sales. That's a lot of cash from a franchise that began in the pages of Marvel Comics and on Saturday Morning Television.

Peter Cullen's impact on the franchise helped make it the pop culture phenomenon it is today. To honor his contributions to film, Cullen was invited to the TCL Chinese Theater in Los Angeles in 2014 to place his handprints in concrete outside the theater, along with his signature, to forever immortalize his name in relation to the filmmaking arts.

The handprint ceremony was done in conjunction with the release of "Transformers: Age of Extinction" on home video, so there were plenty of impressive props and models from the film on hand to underscore Cullen's impressive work with the popular franchise.

If you're familiar with Optimus Prime, you know that he is an imposing figure, but there's not really anything about Prime's physicality that's similar to Peter Cullen — which makes sense, as one is a giant transforming robot and one is a seasoned human actor. Still, it's not uncommon for animated characters to feature some aspect of an actor's appearance.

Optimus Prime didn't look a thing like Cullen for most of his history, but that all changed with the release of "Transformers: Rise of the Beasts." Instead of using the same model for Optimus Prime's face that was used in previous productions, the animators decided it was high time to honor the man who gave Prime his distinctive voice. The VFX artists who animated Prime modeled his face after Cullen, honoring him in a spectacular way. This was revealed by director Steven Caple Jr. in a post on X, formerly known as Twitter, featuring a side-by-side comparison:

Our director Steven Caple Jr CONFIRMS Optimus Prime's FACE is BASED ON PETER CULLEN! pic.twitter.com/F2B86v50mW

— Is Transformers: One out? (@TFHypeGuy) April 29, 2023

When looking at Prime alone, it's not entirely clear that he's modeled after Cullen, but seeing the two side-by-side clinches it. His facial features are slightly more human than they've been presented in the past, and Prime even features a portion of his upper lip that resembles Cullen's iconic mustache.

Peter Cullen has been honored for his work in the "Transformers" franchise, getting to place his handprints into concrete outside Grauman's Chinese Theater in Los Angeles and receiving numerous other accolades. Among those are a Daytime Emmy Award nomination, a Lifetime Achievement Award from the National Academy of Television Arts and Sciences (NATAS), and many more.

One of his most notable achievements came in 2010 with the establishment of the Transformers Hall of Fame. Hasbro established the Hall of Fame to honor the people behind the characters as well as the characters themselves. Cullen was among the first humans inducted into the Transformers Hall of Fame at the annual BotCon, held in Orlando, Florida, in May 2010.

Hasbro threw together an impressive induction video, noting his many performances with a focus on Optimus Prime. Cullen was honored alongside franchise alums Bob Budiansky (Marvel Comics writer), Yoke Hideaki (lead project designer), and Kojin Ohno (toy designer). Alongside the humans, five Transformers were also honored: Optimus Prime, Megatron, Bumblebee, Starscream, and Dinobot. The inaugural class of the Transformers Hall of Fame will forever be immortalized for their work and impact on the franchise that's lasted decades.

Throughout much of his time behind the microphone, Peter Cullen has worked alongside many voice actors. The one he collaborated with more than most is Frank Welker, the voice of Megatron. Of course, if you know anything about "The Transformers," you know all too well that Megatron is the antithesis of Optimus Prime, as the two have been enemies from the beginning.

Like Cullen, Welker played the character across numerous productions, though he also voiced other characters such as Soundwave, Wheelie, Rumble, and more. He's also voiced Megatron in live-action, beginning with "Transformers: The Last Knight" in 2017. Despite playing mortal enemies in their respective roles, Cullen and Welker are the best of friends and first worked together on "Mighty Man and Yukk" in 1979.

The pair often sit for Q&A discussions with fans at conventions, and it can be fun to listen to them voice Prime and Megatron side-by-side. When Cullen received a Lifetime Achievement Award from Children's and Family Emmys in 2023, Welker was the one who introduced Cullen and presented him with the award, which he himself received in 2016.

While animators give the characters movement and definition, it's the voice artist who gives them a personality, and Peter Cullen has demonstrated an ability to do this for all manner of creatures and characters. But like any part of the body, vocal cords can become damaged and worn out, which is something Cullen's mother warned him about early in his career.

Cullen provided the voice for King Kong in the 1976 remake, which required a lot of roaring. He told Collider how this damaged his vocal cords: "I had been coughing up blood because it demanded so much," he recalled. "Anyway, a couple [of] hours after that, I had to go and do Optimus Prime. I don't know how I pulled it off, but I think Optimus Prime sounded about an octave-and-a-half higher than he normally did."

Years earlier, when he was a kid imitating everyone and everything around him, Cullen's mother told him, "Peter, don't do this; you're going to ruin your voice! It's going to stay like that!" Fortunately, that didn't happen, but Cullen had to play it safe throughout his professional career to ensure that he didn't injure his vocal cords the way he did on "King Kong."