Benjamin F. Loan was born in Hardinsburg, Kentucky. He pursued an academic course and received a college education. He studied law in Kentucky, and then moved to St. Joseph, Missouri, in 1838. He was admitted to the bar in 1840 and practiced in St. Joseph.
With the outbreak of the Civil War, he was commissioned as a brigadier general in the Federal Missouri State Militia on November 27, 1861. General Loan participated in counter-guerrilla operations, including the victory against Colonel John A. Poindexter's irregular cavalry at the Battle of Yellow Creek on August 13, 1862. Loan was honorably discharged on June 8, 1863, and returned home.
Loan was elected as an Unconditional Unionist to the Thirty-eighth Congress and reelected as a Republican to the Thirty-ninth and Fortieth Congresses (March 4, 1863 – March 3, 1869). He served as chairman of the Committee on Revolutionary Pensions (Fortieth Congress). He was an unsuccessful candidate for reelection in 1868 to the Forty-first Congress.
He was appointed by President Ulysses S. Grant as a member of the board of visitors to the United States Military Academy in 1869. He resumed the practice of law in St. Joseph, Missouri, and served as delegate to the Republican National Convention in 1876. He was an unsuccessful candidate for election in 1876 to the Forty-fifth Congress.
Benjamin Loan died in St. Joseph, Missouri, and was interred in Mount Mora Cemetery.
- United States Congress. "Benjamin F. Loan (id: L000384)". Biographical Directory of the United States Congress. Retrieved on 2008-08-15