Isachar Zacharie (1825 – September 16, 1900) was a British-American chiropodist (podiatrist), plagiarist, and close confidant and advisor to President of the United States Abraham Lincoln. Born in England, he emigrated to the United States with his family and used falsified educational credentials and fake celebrity endorsements to establish a successful podiatry practice. Zacharie returned to Britain in the 1870s after failing in an attempt to fraudulently bill the U.S. government for podiatric services supposedly rendered by him during the American Civil War.