[citation needed] Willoughby served as president of the Herkimer County Medical Society from 1806 to 1816 and 1818 to 1836.

[1] Willoughby practiced in Herkimer County and was one of the founders of the College of Physicians and Surgeons in Fairfield, where he served as professor of obstetrics.

Willoughby successfully contested the results and was seated for the remainder of the 14th United States Congress, December 13, 1815 to March 3, 1817.

Willoughby was appointed judge of the court of common pleas of Herkimer County in 1805 and served until 1821.

[1] This article incorporates public domain material from the Biographical Directory of the United States Congress