McMichael, a former Civil War officer, was a founding member of the Union League of Philadelphia and the League's 4th president. After the Civil war, McMichael was elected the first Republican Mayor of Philadelphia, serving from 1866 through 1869. At the Union League, McMichael presented Catto, Robert Purvis, Frederick Douglass, Robert Forten and others with a banner honoring their work in the passage of the 15th Amendment in Pennsylvania. The Morton McMichael Elementary School in Philadelphia was named for him.