A few years ago, TIME.com designated K-pop "South Korea's greatest export." While the folks at Hyundai, Samsung and a few other Korean corporations might have something to say about that assertion, there's little doubt that over the past few decades, the treacly, hook-infused musical style has made itself felt, in one way or another, all over the globe.
But few fans of the genre are aware that, more than 50 years ago, three talented young Korean women formed a kind of proto-K-pop group—an ensemble unlike any that American audiences, at least, had ever seen.
Here is how LIFE introduced the trio to its readers in February 1960:
Just one year after leaving Seoul the Kim Sisters [Min Ja, Ai Ja and Sook Ja] are an all-out nightclub hit in the U.S.
The act began 10 years ago when the girls were taught "Ole Buttermilk Sky" and "Candy and Cake" by U.S.troops in Korea. Min Ja sang off-key and Ai Ja chewed gum while she sang, but to the GIs they were the Orient's answer to the Andrews Sisters. Last year an ex-GI named Bob McMackin, who had heard them in Seoul, brought the Kims over [to the States]. The girls learn their songs by rote since they know little English.
In fact, Min-ja, or Mia, was a first cousin to Sook-ja and Ai-ja [the preferred Anglicized spelling of their names), but "Two Kims and Their Cousin" hardly had the ring of the eventual band name. So, in a time-honored entertainment ploy, when they began performing in Seoul in the 1950s, the three took a bit of license and, lo and behold, the Kim Sisters song-and-dance act was born.
In their heyday, the women played nightclubs and other venues all over America and around the world. They were huge hits in Vegas. They appeared on the Ed Sullivan Show more than 20 times. In short, for a number of years in the early to mid-1960s, the Kim Sisters were, without a doubt, the most famous Korean entertainers on the planet.
By the late Sixties, though, all that changed. As Mia Kim told the Korea Times a few years back:
In 1967, all three of us got married. I married a Hungarian musician, Tommy Vig, Sook-ja and Ai-ja married two Italian men. My aunt was a very wise lady because she always told us, "Don't get involved with a man, because if that happens, your career will be over." She was right, you know, the priority was instantly changed and after I gave birth to my son, I wanted to be a full-time mother. Also, as we had husbands in our lives, we began to have disagreements and conflicts, so I moved to Los Angeles with my husband in 1970.
After that, the band played on, but without Mia. The real Kim sisters—and eventually, their brothers—played Vegas for years after the original trio broke up. Ai-ja died in the late 1980s of lung cancer, and the remaining "sisters," Mia and Sook-ja, lost touch with one another.
Still, for a while there, the three beautiful, accomplished young singers and musicians who left the hard times of postwar Korea to seek their fortune in the West had, in fact, found receptive audiences, and more than a little fame, far from their native Seoul.
K-pop or no K-pop, it's a tale worth telling, and remembering.
Liz Ronk, who edited this gallery, is the Photo Editor for LIFE.com. Follow her on Twitter at @LizabethRonk.