Mortimer Dormer Leggett (April 19, 1821 – January 6, 1896) was a lawyer, school administrator, professor, and a general of the Union Army during the American Civil War.

He taught in the Akron and Warren public schools to supplement his income from his legal business, helping to establish the graded-school system now common.

[citation needed] At the beginning of the Civil War, Leggett served as a volunteer on the staff of his friend, Major General George B. McClellan in western Virginia.

President Ulysses S. Grant appointed him as United States Commissioner of Patents in 1871; Leggett held that position until 1881, when he resigned to resume his private practice.

[3] His son, Mortimer M. Leggett, was accidentally killed on October 14, 1873, during an initiation to the Cornell University chapter of the Kappa Alpha Society.