Choe Manri
Choe Manri (?-1445, sometimes spelled Choi Malli) was an associate professor in the Hall of Worthies (집현전 부제학, 集賢殿副提學) who spoke against the creation of hangul (then called eonmun) together with other Confucian scholars in 1444. He made the following submission that year to King Sejong against hangul:

His protest against Hangul

In popular culture
 Portrayed by Kwon Tae-won in the 2011 SBS TV series Deep Rooted Tree.
 Portrayed by Lee Dae-yeon in the 2015 MBC TV series Splash Splash Love.
 Portrayed by Ahn Shin-woo in the 2016 KBS1 TV series Jang Yeong-sil.