Short answers, pulled from the story.
The first historical record of the Incheon area dates back to 475 AD during the reign of King Jangsu of Goguryeo. Historians refer to this early settlement by the name Michuhol, which is supposed to be located on modern Munhak Hill.
Incheon became an international port in 1883 when another historical name of the city called Jemulpo came into wide use until the Japanese annexation. The city center moved from Gwangyo to Jemulpo after the opening of the Incheon port that same year.
North Korean troops occupied Incheon on the 4th of July 1950 before United Nations forces recaptured it on the 19th of September 1950. The Battle of Inchon resulted in a decisive UN victory and launched a United Nations offensive northward.
Incheon was designated as South Korea's first free economic zone in August 2003. The Incheon Free Economic Zone comprises Songdo Cheongna and Yeongjong Island covering a total area of 51,739 acres or 20,938 hectares.
In 2015 Incheon International Airport handled 49,412,750 passengers making it the world's 22nd busiest airport by passenger traffic. There were a total of 305,446 flights to and from Incheon International Airport that year averaging 837 flights daily.