1829 – Born on the 22nd of September in Newburgh, New York.
1848 – Graduated from Princeton University and studied law at Georgetown University.
1851 – Admitted to the bar, moved to Keokuk, Iowa and entered the practice of law.
1857-1858 – Served in the state legislature.
1861 – Commissioned major in the 15th Iowa Infantry and participated in the Civil War battles of Shiloh, Corinth, and Vicksburg.
1864 – Promoted to brigadier general and given command of the 4th Division.
1865 – He was mustered out of service as a major general.
1865-1869 – Belknap was collector of internal revenue in Iowa.
1869-1876 – Served as Secretary of War under President Ulysses S. Grant.
1876 – Impeached by House of Representatives on charges of accepting bribes from Indian post traders (only US cabinet member ever impeached), but resigned before Senate trial.
– He moved to Philadelphia, then returned to Washington to resume the practice of law.
1890 – He died from a heart attack in Washington, D.C., on 13th of October.