By Christian Smith

Led by such expertly stylized groups as the chart-topping BTS, K-pop may be South Korea's biggest cultural export, scaling American music charts thanks almost entirely to fans cultivated on social media.

Six of the top 10 artists on the Billboard Social 50 this week are K-pop stars. The chart tracks artists' social media reach in the United States, where K-pop has exploded despite language and other cultural barriers.

"There was no radio play, there was no TV exposure, there was just no mainstream avenues to access K-pop," said Angela Killoren, the COO of the company that produces KCON, the largest Korean culture convention in the United States. Killoren credits fans' enthusiasm for K-pop stars spread online with the genre's rapid rise outside South Korea.

"Since the very beginning, K-pop artists have really embraced social media and having this direct communication with fans," Killoren said. "I think there's always a lot of trends that you see in K-pop that then later on go on to other genres of music as well."

K-pop entered the American mainstream in 2009, when BoA became the first artist in the genre to chart an album on the Billboard 200. By the time Psy's viral hit "Gangnam Style" took over in 2012, K-pop was a regular part of the American soundtrack.

The ubiquitous success of "Gangnam Style" is one reason why K-pop events like KCON have become so popular in the U.S. Almost 130,000 fans from all over the country converged on the Los Angeles Convention Center and the Staples Center this week to meet their favorite K-pop artists, who rarely tour in the U.S., and to celebrate the latest in Korean culture.

"We knew we had a really passionate fan, and we wanted to figure out something we knew would be an amazing experience for them, but the fan now is creating an amazing experience for everyone else," Killoren said. "The energy and the number of people who come to KCON has just exploded and it’s been great."

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