Daniel Pope Cook (1794-October 16, 1827) was a politician from the U.S. state of Illinois.
He was born in Scott County, Kentucky into a branch of the prominent Pope family of Kentucky. He moved to Kaskaskia, Illinois, in 1815 and began to practice law. Believing his future lay in the nation's capitol, he moved to Washington, D.C., where he hoped his uncle, Nathaniel Pope, a delegate from the Illinois Territory might be able to help. In 1817 he was sent to London to bring back John Quincy Adams, who was appointed to serve as Secretary of State under James Monroe. He became closely acquainted with Adams during the long return trip.
Shortly after he returned from England, he moved back to Illinois where he and a friend purchased The Illinois Herald newspaper from Matthew Duncan and renamed it The Western Intelligencer. Cook became an ardent supporter of statehood and used his newspaper to influence the Territorial Legislature.
He became Auditor of Public Accounts in 1816 and also served as judge of the western circuit. In 1818, he was unsuccessful in his first attempt to be elected to the U.S. House of Representatives, losing to John McLean by only 14 votes for the short term remaining after Illinois became a state. But the state legislature appointed him as the first Attorney General of Illinois. Pope defeated McLean in the general elections later in 1818, and again in 1820 and 1822, and served as the second representative from Illinois (although he was the first to serve a full term). He was defeated by Joseph Duncan when he ran for reelection in 1826. While in Congress, Cook served on the Committee on Public Lands and later on the Ways and Means Committee. He secured a grant of government lands to aid in the construction of the Illinois and Michigan Canal. In 1824, he helped elect John Quincy Adams as president when the election was thrown to the House.
Daniel Cook always suffered from poor health and died on October 16, 1827, at the age of 33 in Scott County, Kentucky. Four years after his death, Cook County, Illinois was named in his honor. He is believed to have been buried in Kentucky.
In 1821, Cook married Julia Catherine Edwards, the daughter of Ninian Edwards, governor of Illinois Territory (and who was related by marriage to the Pope family of Kentucky). Cook's son, John Cook, was a Union general in the Civil War.