Moon Jae-in was elected as South Korea's 19th president, winning a sweeping victory over his conservative and centrist rivals by a wide margin.
The liberal president, who lost narrowly to his predecessor Park Geun-hye in 2012, conveniently won this election as the conservative bloc was brought down by Park's impeachment and arrest over corruption allegations.
Moon advocates the "sunshine policy" of trying to expand inter-Korean cooperation with the Democratic People's Republic of Korea (DPRK).
The rapprochement policy was created by late liberal President Kim Dae-jung and championed by Kim's successor Roh Moo-hyun who governed the country for five years from 2003.
Moon was born on Jan. 24, 1953 in the country's southeastern province of South Gyeongsang. He majored in law at Kyunghee University in Seoul.
As a student activist in the 1970s, Moon was jailed for protesting against the dictatorship of former President Park Chung-hee, father of the impeached Park.
The imprisonment forced him to enlist in the army. He served in the special forces, mainly tasked with demolition operations.
Since 1980s, he worked as a human rights lawyer together with late President Roh. When Roh became president in 2003, Moon served as his chief of staff and senior presidential secretary for civil affairs.
Moon won a parliamentary seat in the April 2012 general elections. He ran for president in late 2012, but he lost to Park by 51.6 percent to 48.0 percent.
He advocated a more balanced diplomatic position between the United States and China, though he considered the U.S.-South Korea alliance as the most significant for defending against threats from the DPRK.
With the impeachment of Park, Moon promised to reform conglomerates, fight income inequality, expand social welfare systems and create jobs for youths, who live amid the super-high unemployment rate.