Commander of the Military Training Agency who defended the gates in Yi In-jwa's rebellion; Lord Hameun, pen name Baegilheon

| Life | 1677 ~ 1735 |
| Era | 조선 후기 |
| Clan | 함평 이씨 |
Yi Sam (1677-1735) was a late Joseon military official of the Hampyeong Yi clan, enfeoffed Lord Hameun. His courtesy name was Wonbaek and pen name Baegilheon. Born in Noseong county, Chungcheong (today's Noseong-myeon, Nonsan), a center of the Soron faction, he studied under Yun Jeung and, being strong and bold, took up martial training on the advice of Minister of War Kim Gu, passing the military examination in 1705.
He served as Pyeongan commander in 1715 and North Hamgyeong army commander in 1719, and for his part as chief of the police force during the Sinim purge became a first-class Busa merit subject. After the Noron took power under Yeongjo he was exiled, but became commander of the Military Training Agency after the 1727 change of government; during Yi In-jwa's rebellion in 1728, as Left Police Commander and Training Commander, he was recorded as a second-class Bunmu merit subject for guarding the gates well and was enfeoffed Lord Hameun.
King Yeongjo is said to have given him the pen name Baegilheon, meaning that the matter was as clear as the sun and his loyalty pierced it. He served as Minister of War and Minister of Works and died in the first month of 1735 aged 59. He is said to have written Gwanseo Jeolyo on the defense of Pyeongan, but it is not extant.
Yi Sam's father Yi Sa-gil studied under Yun Seon-geo, and Yi Sam studied under Yun's son Yun Jeung. His original given name was Song (松); Yun Jeung is said to have changed it to Sam (森), taking a line of Wei Yingwu's poem, after seeing a poem he composed at a mountain temple.
Even after he became an officer, Yun Jeung is said to have urged him by letter not to lose the manners of a scholar and to keep reading the Elementary Learning and the Analects.
During Yi In-jwa's rebellion in 1728 Yi Sam held the gates as Left Police Commander and Training Commander. In 1731 a newly appointed Hwanghae naval commander refused to greet him on the ground that he was linked to a traitor; King Yeongjo refused his resignation and gave him the pen name Baegilheon.
The Jwagye Budam, however, remarks that his narrow temper made him disliked by many.
In Nonsan there are the Baegilheon portrait hall enshrining his portrait and the head house, with his tomb behind it. His descendant Yi Dal-heon published the collected works Baegilheon Yujip in 1949, and together with Mallok, discovered in 1997, they were translated into modern Korean in 2023 by the Korea Confucian Culture Promotion Institute.
Seokjong-ri, Sangwol-myeon, Nonsan, South Chungcheong (behind the Baegilheon portrait hall)