By Mark Stone, Asia Correspondent
Conservative politician Park Geun-hye has become South Korea's first female president, after narrowly beating her liberal opponent.
Moon Jae-in conceded on Wednesday night to the daughter of late dictator Park Chung-hee, several hours after polls closed in the close fought race.
Her victory came despite analysts' speculation that high voter turnout would favour Mr Moon.
Mr Moon is the son of North Korean refugees and a former human rights lawyer while she is the daughter of a former dictator.
It is understood that more than 70% of the eligible population braved temperatures of well below zero to vote.
The leadership of North Korea still remains a problem for South KoreaInitial predictions during the counting phase were of a race too close to call.
Ms Park is the first female president of a nation which is still heavily dominated by men.
According to analysts, her victory is likely to shatter a national 'glass ceiling' and will be seen as a massive step forward for women's rights.
Ms Park's rival Moon Jae-in was once a special forces soldierShe is the daughter of General Park Chung-hee, the former South Korean dictator whose autocratic rule over the country lasted for 18 years before he was assassinated by his own spy chief in 1979.
Despite his dictatorship, he is widely credited for pulling South Korea out of poverty and turning it into the economic and technological success that it is today.
Pundits said Ms Park's vote was boosted by a conservative base of older voters with fond memories of South Korea's rise from poverty.
Mr Moon was once jailed for his opposition to Ms Park's father's rule - he is the son of North Korean refugees who fled to the south during the Korean War.
Ms Park's challenges are numerous: she is faced with a belligerent North Korea, a slowing economy and rising welfare costs.
On North Korea, both candidates had a desire for further engagement though Ms Park's approach is more cautious. Mr Moon had promised to resume aid to the country without preconditions.
A British diplomat in Seoul described to Sky News the difference between the two approaches on North Korea as: 'Stick then large carrot from Park; large carrot then small stick from Moon.'
Ms Park, 60, has wide support with women voters in South KoreaRelations between the North and the South are tense. The two are still technically at war. The border between the two - the 38th parallel - is the most fortified and heavily mined border in the world.
The relationship worsened with the shooting by North Korea of a tourist from the South in 2008, the sinking of a South Korean warship; an incident which North Korea says it had nothing to do with and the shelling of a South Korean island in 2010.
Although North Korea remains a pressing issue for Ms Park, it did not play heavily in the campaigning despite the successful launch of a three-stage rocket by the North last week.
"It has been very much sidelined," Brendan Howe, a professor of International Relations based in Seoul told Sky News.
"Both sides want engagement but neither side put it at the forefront of their campaign. It has not a massive issue in the election." he said.
An equally pressing issue for Ms Park is the widening gap between rich and poor in South Korea and the dominance of family-owned conglomerates like Samsung and Hyundai.
Wooing the crucial centralist voters resulted in significant overlap between the two candidates' policies during campaigning. They had both talked about 'economic democratisation' - reducing the social disparities that have come with rapid economic growth.
Ms Park is now one of a number of new leaders in the region. Japan has recently voted in right-wing candidate Shinzo Abe and China's new communist leadership, with their opaque direction, will take office in March.