Yi Sugwang was born to a wealthy, aristocratic family in 1563, and was offered the finest education his parents could afford.
In the wake of Seven-Year War, he was stationed in Jogyeong, Gyeongsang province, where he was given command of a small army contingent.
In 1614, he would write about his military experience, noting that the Joseon forces had "too many sajok (families of yangban or scholar officials), idlers, vagrants and too few people liable for service.
In his later works - Jibong Jib (지봉집) and Chaesin Jamnok (채신잡록)- he placed less emphasis on Confucianism and emphasized adopting western knowledge to strengthen the nation.
His work also dealt with the subject of moderate political and economic reforms to improve the living standards of the peasants, which had deteriorated following the Seven-Year War, and the bureaucracy.
He also implemented welfare policies, believing that the Way of Heaven was found among the people and the most noble endeavour was to feed and clothe the poor.