He learned English and theology at Yookyoung Park, went to the United States to live as a diplomat, and returned to Korea to serve as a pro-Russian politician until the 1896 Agwan Pacheon incident, where King Gojong and his crown prince took refuge at the Russian legation in Seoul.

[2] Lee was a founding member of the Independence Club established in 1896 and belonged to the "reform faction" which wanted to Westernize Korea and to open the country to foreign trade.

The incident happened on December 22, 1909, when he and other targeted officials were attending a memorial service in Jong-hyeon Catholic Church (present-day Myeongdong Cathedral) for the recently deceased King Leopold II of Belgium.

He died in February 1926, received a grand funeral with the Governor-General at that time, Saitō Makoto in attendance, and was posthumously awarded the Supreme Order of the Chrysanthemum.

[9][7] Knowing that his grave would likely be vandalized because of his actions, Lee Wan-yong purposely chose a plot of forest land in Iksan, North Jeolla Province, as his final resting place because it would be difficult for people to find.

However, his grave is still vandalized to the point that police officers were dispatched to guard the area during the Japanese colonial era.