Moon Jae In, who became South Korea's president Wednesday after winning an election as standard bearer of the Democratic Party of Korea, was a human rights lawyer and chief aide to the late President Roh Moo Hyun.

The 64-year-old entered politics by winning a parliamentary seat in the southeastern city of Busan, his hometown, in 2012. In the same year, he made his first bid for the presidency, as a candidate representing the then main opposition Democratic United Party, but lost to Park Geun Hye of the then ruling Saenuri Party.

The conservative camp has criticized Moon for being too radical and too soft on North Korea.

Moon was born on Geoje Island in South Gyeongsang Province in 1953 to poor parents who were refugees from North Korea. He finished middle and high school education in Busan.

While majoring in law at Kyung Hee University in Seoul, he led a protest rally against the dictatorship of then-President Park Chung Hee, for which he was arrested and expelled in 1975. He was assigned to serve in the Special Forces to fulfill his military service.

He returned to school in 1980, but was arrested again for violating martial law. After passing the bar exam and eventually being released, Moon returned to Busan after not being appointed as a judge, and decided to become a lawyer.

At this time, he met Roh Moo Hyun, who was also a human rights lawyer, and the two handled nearly all of the cases related to labor and human rights in Busan.

Moon and his wife Kim Jung Sook have a son and a daughter.