David Rice Atchison (August 11, 1807 – January 26, 1886) was a prominent Missouri politician, lawyer, and U.S. Senator whose career shaped the early political landscape of northwest Missouri. Born in Frogtown near Lexington, Kentucky, he moved to Liberty, Missouri around 1830, where he established a successful law practice.

Atchison served in the Missouri House of Representatives beginning in 1834 and again in 1838. In 1841, he became judge of the Platte County Circuit Court, placing him at the center of legal and civic development in the newly formed Platte Purchase counties.

He entered national politics in 1843, when he was appointed—and later elected—to the United States Senate, serving until 1855. Atchison became especially influential as President pro tempore of the Senate, a role he held multiple times between 1846 and 1854.

Atchison played a major role in the sectional politics of the 1850s, supporting the Kansas‑Nebraska Act and the repeal of the Missouri Compromise. His strong pro‑slavery stance ultimately cost him a third Senate term.

He spent his later years in northwest Missouri and died near Gower in 1886. Atchison is buried in Greenlawn Cemetery in Plattsburg, where a memorial honors his long public career.