His views on North Korea differ greatly to Trump's
Democratic Party nominee Moon Jae-in has been elected as the next president of South Korea.
The eldest son of North Korean refugees, and a successful human rights lawyer in his own right, Mr Moon wants to shake up the relationship between North and South Korea - opting for a far less aggressive stance than US President Donald Trump.
Beyond his vow to address the North Korea issue - who is the new left-leaning leader of South Korea?
In 1972, Mr Moon was arrested for his involvement in student activism, leading the protests against former president Park Chung-Hee's authoritarian rule.
He was sent to jail, where he passed the bar and was eventually released.
Mr Moon was conscripted to the South Korean army in 1976.
He took part in South Korea's military operation in response to the killing of two US officers, whom North Korean soldiers attacked for trimming a tree.
Six years later, he and his friend - and another future president - Roh Moo-hyun opened a law firm in the city of Busan, which focused on human and civil rights issues.
His former colleague Seol Dong-il remembers him for having "a distinctly nerdy style", spending hours preparing for court.
But Mr Seol also remembers the care with which he treated those who came to him for help.
"When workers sought advice from him, Moon used to sit down for hours to listen to them," Mr Seol told Reuters news agency.
Mr Moon and Mr Roh became leading figures in the pro-democracy movement which swept the country and led to South Korea's first democratic election in 1987.
Mr Moon acted as one of Mr Roh's top advisors upon his election in 2003, earning him the nickname of 'Shadow of Roh'.
On the campaign trail, Mr Moon was described as being "ridiculously awkward" by former politician Choi Nak-jeong. It was an assessment that Mr Moon later agreed with.
"I always felt uncomfortable," he wrote in 2003. "I felt that the job was not suitable for me, as if I was wearing clothes that did not fit. I always thought 'I will go back to my place, a lawyer'."
In 2007, he came under fire over allegations that the government of then-President Roh had consulted North Korea before abstaining from a UN vote on a human rights resolution against the North in 2007.
Mr Moon has denied the allegations.
In 2009, Mr Roh took his own life after leaving office as corruption investigators closed in over allegations he had accepted $6m ($4.6m) in bribes.
The incident left a lasting impact on Mr Moon. Writing in his 2011 memoir, 'Moon Jae-in: The Destiny', he said:
"When I drink a little, I sometimes recall my old days. Then I ask myself: 'What does Roh Moo-hyun mean in my life?'
"He really defined my life. My life would have changed a lot if I didn't meet him. So he is my destiny."
Mr Moon re-entered public life in 2012, running in the presidential elections against Park Geun-hye. He lost, but did win the MP's seat in Busan.
More than two decades after he lead the country to its first democratic elections, Mr Moon secured the presidency in this year's election following Park's impeachment.
Mr Moon has been open about his desire to rebuild relations within the Korean peninsula.
Among his goals as South Korea's president, Mr Moon wants to “negotiate sincerely” with the US and China over the recent deployment of THAAD, a US missile defence system designed to thwart attacks by North Korea.
China has urged the new president to scrap the system, claiming its powerful radar could be used to spy on its missiles.
He also said he would also be willing to meet North Korean President Kim Jong-un if it meant bringing "lasting peace" to the area.
“I am willing to go anywhere for the peace of the Korean peninsula if needed. I will fly immediately to Washington, I will go to Beijing and I will go to Tokyo. If the conditions are right, I will go to Pyongyang.”
He faces his fair share of stumbling blocks. In an interview with Reuters earlier this year, President Trump said that he plans to take a hard line with South Korea over trade and the cost of deploying THAAD.
The president said during the interview that he thought Washington’s free trade agreement with South Korea was such a bad deal for the US that he would withdraw from it if they were unable to renegotiate one to his liking.
"It's unacceptable. It's a horrible deal made by Hillary. It's a horrible deal. And we're going to renegotiate that deal, or terminate it," he said. “It's a great deal for South Korea. It's a terrible deal for us."
Trump also said that he expected South Korea to pay for THAAD.
In a book released this year, Mr Moon revealed he still dreamed of returning to his parent's North Korean home town, Hungnam.
"I was thinking I wanted to finish my life there in Hungnam doing pro bono service," he wrote. "When peaceful reunification comes, the first thing I want to do is to take my 90-year-old mother and go to her home town."