When Sue Kim arrived to the U.S. after leaving her home in Korea, decimated by war, she found herself performing at the storied Thunderbird and Stardust hotels in Las Vegas. It was 1959, and despite singing songs like Tony Bennett’s “I Left My Heart in San Francisco” to large crowds, Kim didn't know much English. She was a Korean performer recruited to sing American songs as part of the Kim Sisters band, and most of her English vocabulary had been learned from the TV western Gunsmoke.

Sue Kim's home, circa 1951. Image courtesy of Sue Kim

Before coming to the U.S., Kim had lived in a brick storage unit with her family and 22 other people beginning in 1951. Seoul was burning, and North Korean soldiers had torched her family’s home. It was June of 1950 and the beginning of the Cold War when Soviet-backed North Korea first crossed the 38th parallel to invade South Korea, aligned with the West. A month later, the U.S. would enter the Korean War. The family’s unit didn’t have a bathroom, and Kim and the occupants would go days without eating. Her mother, the legendary Korean singer Lee Nan-Young, took to performing for U.S. troops in military camps. The soldiers would offer her whiskey or cases of beer, which the family would then exchange for rice on the black market.

With seven children, Kim’s mother realized even more performances could mean more food. “My mother had tremendous stress and pressure,” Kim tells HISTORY. “Her children were all crying out for food.” Armed North Korean soldiers had abducted their father, a famous composer, from the family’s home; a North Korean defector later informed them that he had been put in jail and was killed. (“We don’t know how true this was,” Kim says.) Out of this need to help the family, the Kim Sisters were born.

Though today’s K-pop is a different genre altogether, the Kim Sisters are considered to have laid roots as one of the first popular Korean crossover groups—selling out U.S. shows and garnering press in magazines like Life and Newsweek. They also went on to become the act with the most performances ever on the Ed Sullivan Show, Kim says, with a 22-appearance contract.

The group was made up of Sue (Sook-ja), who was 9 when it started, her sister, Ai-ja, 8, and their cousin, Mia (Min-ja) Lee, 9. Kim’s mother had begun training them by finding American records at illicit markets. From 1953 to 1958, they’d learn the songs and perform at various U.S. military camps. Their English was limited, but the troops were drawn to their presence and the fact the girls could play instruments ranging from bass guitar to tenor saxophone to drums.

The Kim Sisters performing with many different instruments on the Hollywood Palace on January 15, 1966. ABC Photo Archives/Getty Images

Kim, herself, played 13 instruments. “That was very unusual at that time,” she says. “We didn’t understand what we were singing. We couldn’t speak English, but that’s what a performer does. You act like you know what you were singing.”

In 1959, the group made its way to the U.S after being connected with Tom Ball, a Las Vegas producer. Ball had heard about the girls from American soldiers, who reported that they were young phenoms whose unique musical talents and charm would dazzle U.S. audiences, Kim says. In Vegas, the teens were hooked up with a manager, and given four weeks to make it big and sell out shows at the Thunderbird. And they succeeded.

After their residency at the Thunderbird, the Kim Sisters would go on to spend 15 years at the Stardust, five years at the Las Vegas Hilton, and 15 years at the Holiday Casino.

The Kim Sisters’ brand of K-pop doubled as political propaganda

The Kim Sisters’ first big act at the Thunderbird Hotel was called “China Doll Revue.” Although the show played up their foreignness, Kim believes their acts were not “Orientalizing” and that viewers were genuinely interested in learning about the Sisters’ culture. “We were ambassadors. People would say they liked our kimono. We’d say, ‘No, it’s a hanbok—a traditional Korean dress,’” she says.

“The U.S. certainly welcomed the idea that the Kim Sisters were becoming celebrities,” says Roald Maliangkaij, director of the Korea Institute at Australian National University. With public support for the war eroding, he says the Kim Sisters’ story and success was used as “propaganda” and helped validate America’s decision to defend South Korea.

The Kim Sisters also showed what achieving a version of the American dream could look like. “They are arguably one of the prime instigators or influencers in terms of migration," he says. "For Koreans, they are the image of what migration might offer them.”

The Kim Sisters featured on the front cover for the Chicago Daily Tribune. Image courtesy of Sue Kim

The first Asian group to produce music in the U.S., the Kim Sisters released their inaugural album in 1963 after recording in Nashville, Kim says, stating that it never actually took off. She attributes it to the fact that the group didn't have a chance to do promotional travel due to financial constraints. "If we stopped working to promote the album, there was no money coming in."

They still had to send money back home, and Kim was now in charge of taking care of five siblings because her mother had also sent her three brothers to the United States to form the Kim Brothers, a group that ultimately didn't experience the same level of success as the sisters.

Up until releasing their album, the Kim Sisters had been singing primarily rock, pop, and ballads. Many compared them to the McGuire Sisters, known for their sweet voices, identical hairstyles, and hit records in the 1950s and ‘60s.

But Kim’s managers pushed the group to sing country and western songs for their album. "Where is Nashville? What was it? I didn't know at the time!" Kim says. She believes their lack of knowledge about the genre was another reason why the album never soared. They later released other records and singles in Korea and the United States.

Kim says she felt the group had truly made it when they started appearing on programs like The Hollywood Palace, a variety show on ABC. But she most appreciated the small gestures, like when Americans would applaud for them on the street. She was touched when a fan recently sent her an old room key as a memento of the now shuttered Stardust resort and casino.

Another career high for her was when she brought her mother to the U.S. in 1962, and they performed together on the Ed Sullivan Show. "We all sang harmony," she remembers. Her mother later died of heart failure in 1965. "She had struggled to take care of seven kids and I think she thought she finally did her job and she let go."

Their shows and relative success did allow her to meet her husband. In 1968, she married New Yorker John Bonifazio, a casino magnate whom she met at one of her performances, and had two children. Kim and Mia Lee eventually had a falling out over their husbands’ involvement in the group, Kim says. Lee ended up leaving the group in 1973. Sue’s sister and other bandmate, Ai-ja, died from cancer in 1987, and Sue stopped performing in Las Vegas in 1995. She’s now a real estate agent in the city.

The Kim Sisters’ parallels with modern K-pop

After the Kim Sisters became stars in America, there were a number of sister-based acts in South Korea that tried to emulate them, including the Kimchi Kats, the Pearl Sisters, the Chong Sisters, and the Yi Sisters. These groups created unique combinations of Korean folk songs blended with Western music like the Beatles, hard rock, British pop, Bob Dylan, and Led Zeppelin.

Maliangkaij says Korean groups of the moment loved American-style lyrics focused on introspection and individualism, though “anything that spoke about thinking about your own life or being solo," was outlawed at the time, he says.

This golden age of early K-pop was short-lived. Beginning in 1975, then-President Park Chung-Hee's "Purification of Popular Music Measures" aimed at ending this hybridization of Korean and Western music by banning sales of the form of K-pop. The measure was part of a national law that was passed to allow the government to arrest anyone who acted against South Korea, according to the book Made in Korea: Studies in Popular Music.

The Kim Sisters playing banjos in the 1960s. The Kim Sisters are considered to have laid roots as one of the first popular Korean crossover groups. Image courtesy of Sue Kim

"Park was not only autocratic but puritanical,” says John Lie, a sociology professor at University of California, Berkeley, whose work focuses on Korean identity and diaspora. “He sought to curb American decadence—for example, women thinly clad and gyrating—and to promote Korean nationalism.”

Maliangkaij says attempting to eradicate the genre wasn’t exactly a success, pointing out young Koreans still found ways to consume it. “The black market continued to be active,” he notes. After Chung-Hee was assassinated in 1979, the underground K-pop scene bubbling below the surface during the purification measures rose to greater prominence.

Even today, however, "K-pop groups tend to avoid suggestive material as matter of business strategy,” Lie says. “They are trying—or their producers and managers are trying—to present kinder and gentler versions of the more outré U.S. acts to capture a large slice of the world market. Fewer tattoos, avoidance of violence and drugs," he says.

Similarly, Kim says maintaining a wholesome image to help the Kim Sisters achieve commercial success was simply a matter of providing for her family—a wartime work ethic that still permeates culture in Korea today. "We sent money for my family to live on. We made a lot of money but had to spend a lot of money, too."

Maliangkaij says some of the similarities between the Kim Sisters and today’s K-pop lie in having an inspiring background story, plus a uniform look. “Looking cute—that is something K-pop is very much selling today. It’s not selling wonderful voices, but visual impact. The emphasis on the showmanship and the success the Kim Sisters had certainly influenced the Korean landscape,” he says.

Kim believes her group forged a path for today's K-pop stars. "All those kids—I'm sure they know of us. Someone is feeding them our story. It's a struggle to learn English and work hard and never date until you’re 23. Korean people—we advance and we have the drive."

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