William Prentice Cooper (1895 - 1969) was an American politician who was Governor of Tennessee from 1939 to 1945.

A native of Bedford County, Tennessee, he attended Vanderbilt University and then Harvard University. After service in World War I, he opened a law practice in 1921, and served in the Tennessee House of Representatives in 1923 before being elected district attorney. In 1936 he was elected to the Tennessee State Senate. He attracted the favorable attention of Memphis political boss E.H. Crump, who had experienced a falling-out with his one-time protege, Governor Gordon Browning. With Crump's help, Cooper achieved the Democratic nomination for governor in August, 1938. At this point in Tennessee history, the Democratic nomination for statewide office was considered "tantamount to election", as it was in much of the South in that era.

Cooper was Tennessee's wartime governor during World War II, which brought about the basis for the greatest social change in the history of the state up to that point. Large facilities were built, including Fort Campbell, most of which is in Tennessee despite its Kentucky address, some POW camps, and the Oak Ridge facilities where the atomic bomb was developed. Of course, the state government under Cooper played only a supporting role in these activites, which were under the direction of the federal government's War Department.

Cooper was also an advocate for education, and during his tenure the state began to provide textbooks for students in the lower grades without requiring that their parents purchase them, a major change. He was also dedicated to higher teacher pay, but very limited in how he could provide for this due to the state's very limited tax base. He was also dedicated to public health, and during his tenure a statewide network of tuberculosis hospitals was built which served the state for about three decades.

Cooper served three consecutive two-year terms. Also during his tenure, the state debt was greatly reduced. After his third term expired he left elective politics. Staying active in public service, Cooper was later U.S. ambassador to Peru. He served as a delegate to the limited state constitutional convention in 1953, which proposed several major changes which were subsequently adopted by the voters, including, perhaps most notably, the extension of the gubernatorial term from two to four years. From then on, he was regarded as something of a Democratic elder statesman in the state. Prentice Cooper State Forest, atop Signal Mountain near Chattanooga is named in his honor.

Cooper, a bachelor while in office, later married. His son Jim Cooper, born in 1955, has served twice in the United States House of Representatives. In 1984 he was elected in Tennessee's Fourth Congressional District, replacing Al Gore, who ran for and won a seat in the United States Senate. In the November election he defeated Cissy Baker, the daughter of then-Senate Majority Leader Howard Baker, in a race featuring the offspring of two famous Tennessee political figures. He served the Fourth District until 1995, not running for re-election in 1994 in order to run against Republican nominee Fred Thompson for the balance of Al Gore's Senate term remaining after he became Vice President of the United States. Losing in a landslide, he returned to private life, and later moved to Nashville, where he was elected to a new House term from the Fifth Congressional District in 2002.