South Korea's presidential election comes after country’s former leader was impeached for imposing martial law

Lee Jae-myung, the liberal South Korean politician favoured to become the country's next leader, has overcome a knife attack, martial law and criminal charges on his unexpected path back toward the presidency.

By the standards of South Korea’s teeming metropolises, Sejong is not much of a city. With a population of 400,000 people, Sejong, a planned city located about 100km (62 miles) south of Seoul, does not even crack the top 20 urban centres.