Short answers, pulled from the story.
King Sejong the Great of the Joseon Dynasty created Hangul in the 15th century. The script was originally called Hunminjeongeum and was designed to ensure that common people could read and write.
The linguistic homeland of the Korean language is suggested to be somewhere in contemporary Manchuria. Proto-Koreans expanded into the southern part of the Korean Peninsula around 300 BC.
The North Korean government abolished Hanja in writing in 1949. Hanja continues to be taught in schools in North Korea while usage in South Korea is mainly reserved for specific circumstances such as newspapers and scholarly papers.
The United States Department of Defense places Korean in Category IV requiring 64 weeks of instruction to bring an English-speaking student to a limited working level of proficiency. This is in contrast to just 26 weeks for Category I languages like Italian, French, and Spanish.
Three models of language and gender have been proposed for Korean: the deficit model, the dominance model, and the cultural difference model. The deficit model sees male speech as the default, the dominance model sees women as lacking power, and the cultural difference model attributes speech differences to upbringing.