In 1888, Yi was appointed as Aide-de-camp to William McEntyre Dye, the headmaster of the Yunmu Military Academy.

[3] The night that Empress Myeongseong was assassinated by the Japanese ronins and soldiers, Yi reported the conspicuous circumstance of Gyeongbokgung to William McEntyre Dye, and Afanasy Seredin-Sabatin.

As the conspicuous sounds of bullets came closer to him, Yi wore a civilian garment and fled.

[7] In July 1897, Yi was appointed as a chief of ambassador (영선사 장) to Qing dynasty.

[20] In October 1902, Yi visited Japan to watch Fall training of the Imperial Japanese Army.

[24] When he thought that the Empire of Japan was trying to kidnap him, Yi hided in the French legation then refuged to Shanghai.

Did well and always kept out of trouble until he got scared and took refuge at Sontag's with Hyen Sang Kun, and was suspected and had to flee to China where he was injured by a fall from his horse and became an opium fiend.

'[29] William Franklin Sands wrote, 'Another member of the circle was Ye Hak Kiun, General Dye's assistant and now head of the military academy.