"I remember reading that within three square miles, there's like 115 Korean churches in Koreatown," said Young Lee, a pastor at Hillside L.A. church.
For Grace Kim, age 90, that story began in present-day North Korea.
"[My] great, great grandparents became Presbyterian. That was a long, long time ago," said Kim, a proud fourth-generation Presbyterian.
Nearly 30% of South Koreans identified as Christian in 2010, according to the Pew Research Center, a huge jump from just 1% in the early 20th century. Pew pinned Christianity's rapid growth on the efforts of missionaries and churches in the country.
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Kim said she was born in China after her family fled the Japanese occupation of Korea.
"When I lived in Shanghai, church was our home. We were there all the time in the underground independence movement," she said. "It was so beautiful. I'm really blessed."
Kim's faith has remained constant through life's trials: Returning to Korea and fleeing to the south during the Korean War, caring for children who lost their parents in the conflict and later immigrating to the U.S. in her 30s.
She started off in Buffalo, New York, but in the 1960s, the city had no Korean churches and her family went to the local American church. She later moved to Northern California with her husband, the late Dr. Luke Kim.
"I liked the people, church. People there were so wonderful to me," she said.
Kim was a high school counselor and her husband was a clinical psychiatrist and professor. They also helped support new Korean American churches, institutions that have been social, cultural and educational pillars for decades.
The first Korean Presbyterian church was formed in Los Angeles in 1906.
"The first Korean church is in 1903 in Hawaii, then the first Korean church in the mainland is 1904," said Ray Kim, a retired Methodist reverend who was a pastor at the latter church for 11 years.
"The pastor's role, first of all, is helping their spiritual needs. Secondly, helping, their settling down in USA," Kim said.
By 2010, 71% of Korean Americans living in the U.S. identified as Christian, including 61% who are Protestant and 10% who are Catholic, according to Pew.
Pastor Lee was born in Seoul, South Korea, and his family immigrated to Los Angeles 48 years ago.
"I come from a long line of pastors in my family, so naturally when we moved here, we got connected to church," Lee said.
Churches remain a cornerstone of support for immigrants.
"Even recently, we would get calls from random people that just moved from Korea asking for assistance, if we can help them find jobs," he said.
Danny Kim is the youngest of Luke and Grace Kim's two children, following in their faith-filled and justice-seeking footsteps.
"Whether it's serving a neighbor in need or social injustice -- which has been also another big part of my life growing up -- it's just so inspiring," he said.
As a nonagenarian, Kim is a tireless activist. She and Dr. Luke Kim were also part of a core group that led the successful effort for the acquittal of Chol Soo Lee, who was wrongfully convicted of murder.
"I was so happy. We won. He was in prison for 10 years. Can you imagine? Young man, mistaken identity," she said.
Kim recently helped organize a rally of hundreds of people to support neighbors who received a racist hate letter in her community. "We have to fight, and fight does not mean screaming, yelling and fighting. But we must work for justice. We should not be quiet."
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