Isaac N. Arnold

Isaac Newton Arnold (November 30, 1815, Hartwick, New York - April 24, 1884, Chicago) was an American politician and biographer. He served two terms in the United States House of Representatives and was known for his support of the abolition of slavery.

Arnold attended the Hartwick Seminary in his hometown of Hartwick, New York. He studied law and was admitted to the bar in 1835. He moved to Chicago in 1836 and began a successful law practice, during which time he made the acquaintance of fellow Illinois lawyer Abraham Lincoln.

In 1842, Arnold was elected to the Illinois House of Representatives as a Democrat. He served three terms, and then left the Democrats to become an organizer of the Free Soil Party in Illinois. Arnold served one more term in the state house from 1855-56 under the Free Soil banner, and then won election to the U.S. House as a Republican in 1860. He was reelected in 1862. He was a strong supporter of President Lincoln during his tenure in Congress.

In March 1862, Arnold introduced a bill to abolish slavery in U.S. territories, which became law in June 1862. In February 1864, he introduced a constitutional amendment to abolish slavery throughout the United States. Although the bill did not pass in the 1864 session, it was renewed in 1865 and adopted as the Thirteenth Amendment to the United States Constitution.

Arnold, facing a strong challenge in 1864 from Democrat John L. Scripps, withdrew from the race in favor of John Wentworth, and accepted a presidential appointment as an auditor in the Treasury Department. He left that post and returned to his law practice in 1866. At the same time, he began work on a biography of Lincoln. Arnold published The History of Abraham Lincoln in 1866, followed by the highly-regarded The Life of Abraham Lincoln in 1884. He also wrote The Life of Benedict Arnold (1880).

References

• American National Biography, vol. 1, pp. 636–637.
• Isaac N. Arnold at the Biographical Directory of the United States Congress
• James A. Rawley, "Isaac Newton Arnold, Lincoln's Friend and Biographer", Journal of the Abraham Lincoln Association, winter 1998
• Hartwick College profile
• Isaac N. Arnold at Find a Grave