Caleb Blood Smith (April 16, 1808-January 7, 1864) was an American journalist and politician. Born in Boston, Massachusetts, he emigrated with his parents to Ohio in 1814, was educated at Cincinnati College and Miami University, studied law in Cincinnati and in Connersville, Indiana, and was admitted to the bar in 1828. He began practice at the latter place, established and edited the Sentinel in 1832, served several terms in the Indiana legislature, and was in the United States Congress in 1843-'9, having been elected as a Whig. During his congressional career he was one of the Mexican claims commissioners. He returned to the practice of law in 1850, residing in Cincinnati and subsequently in Indianapolis. He was influential in securing the nomination of Abraham Lincoln for the presidency at the Chicago Republican convention in 1860.
Smith was appointed by him U.S. Secretary of the Interior in 1861 by Lincoln as a reward for his work in the presidential campaign. He was the first citizen of Indiana to hold a Presidential Cabinet position. However, Smith had little interest in the job and, with declining health, delegated most of his responsibilities to Assistant Secretary of the Interior John Palmer Usher. After Smith resigned in December, 1862, Usher became Secretary. Smith resigned to become United States circuit judge for Indiana.