Yu Seong-ryong

Yu Seong-ryong (1542–1607) was a scholar-official and Prime minister of the Joseon Dynasty of Korea. He was a member of the "Eastern faction", and a follower of Yi Hwang.
Yu was born in Uiseong, in Gyeongsang province, to a yangban family of the Pungsan Ryu clan.

Biography
Yu is said to have been so precocious that he absorbed the teachings of Confucius and Mencius at the age of 8. In 1564 the 19th year of Myeongjong, he passed the Samasi examination, and in 1566 he passed the Mun-gwa at a special examination, and then took the post of Gwonji bujeongja (권지부정사, 權知副正字). He held various other positions and in 1569 he joined the imperial birthday mission to Ming as a Seojanggwan (서장관, 書狀官), returning to Korea the following year.

In 1590, He was appointed Uuijeong (Third State Councillor) and Pungwon Buwongun (풍원부원군, 豊原府院君). In 1591, He was promoted to Jwauijeong (Second State Councillor) and Ijo Panseo (이조판서, 吏曹判書). However, "Eastern faction" was split as "Southern faction" and "Northern faction". Because of "Western faction's disciplinary punishment, which was led by Jeong Cheol. He was a member of the "Southern faction".

He was in the rank of provincial Dochechalsa (도체찰사, 都體察使) when the Imjin War broke out in 1592 also he was appointed Yeonguijeong, the Chief State Councillor or Prime Minister. Yu Seongryong accompanied the royal family at Hanseong to Uiju.
In this capacity, he oversaw all military units and called leaders like Yi Sun-sin and Gwon Yul to battle. He also fought on the Korean-Chinese allied forces side in the Siege of Pyongyang. He suggested of establishment the Hunnyeon Dogam (훈련도감, 訓鍊都監, Training capital garrisons).

In 1598, he was ousted by the "Northern faction". King Seonjo rehabilitated him, however, he refused to take office as a minister in 1600. In 1602, Joseon government bestowed honors upon him, as the second rank of Hoseong Gongsin (호성공신, 扈聖功臣), and appointed Pungwon Buwongun again.
After which he spent his time on political writing before died in 1607.
Yu's major writings are preserved in the Seoaejip (The anthology of Seoae, 서애집, 西厓集), Jingborok (The book of Correction, 징비록, 懲毖錄), and minor writings as Hwanghwajip (황화집, 皇華集), Jeongchungrok (정충록, 精忠錄). Yu Seong-ryong was enshrined in the Byeongsan Seowon and Hogye Seowon in Andong, North Gyeongsang.