Preston, the grandson of
Col.
William Preston—the namesake of
Prestonville, Kentucky—was born in
Louisville, Kentucky.
Francis Preston was his uncle. His sister Henrietta married
Albert S. Johnston in 1829. He pursued preparatory studies and graduated from
St. Joseph's College in Kentucky. He attended
Yale College in 1835 and graduated from the law department of
Harvard University in 1838. After graduation from Harvard, Preston was admitted to the bar and commenced practice in Louisville in 1839. He served as
lieutenant colonel of the 4th Kentucky Volunteers in the
Mexican–American War from 1847 to 1848. After the war, he was a delegate to the State constitutional convention in 1849 and a member of the
Kentucky House of Representatives in 1850. Subsequently, he served in the
State senate 1851–1853. He was elected as a
Whig to the
Thirty-second Congress to fill the vacancy caused by the resignation of
Humphrey Marshall and reelected to the
Thirty-third Congress and served from December 6, 1852, to March 3, 1855. He stood again for another term in 1854 but was unsuccessful. President
James Buchanan appointed Preston as
Envoy Extraordinary and Minister Plenipotentiary to Spain in 1858. He resigned as ambassador in 1861 at the outbreak of the
Civil War. Although his home state of Kentucky did not
secede from the
Union, Preston would serve the South. In November 1861, the provisional government for Kentucky appointed he, Henry C. Burnett and William E. Simms as commissioners to treat with the Confederates States government for the admission of Kentucky into the Confederacy. Shortly thereafter, Preston was made a colonel and became volunteer aide-de-camp to his brother-in-law,
Albert Sidney Johnston, who then had his
Army of Central Kentucky quartered at
Bowling Green. Preston attained the rank of brigadier general in April 1862. He commanded a brigade in
Breckinridge's division of
Hardee's Corps at the
Battle of Stones River, and during the
Army's subsequent retreat to
Tullahoma. On April 28, 1863, Preston was ordered by Secretary of War
Seddon to southwest Virginia to relieve
Humphrey Marshall and assume command of the District of
Abingdon. That fall, Preston commanded a division at the
Battle of Chickamauga. He was appointed Envoy Extraordinary and Minister Plenipotentiary from the
Confederacy to
Maximilian, Emperor of Mexico in 1864. After the war, he again served as a member of the Kentucky State House of Representatives in 1868 and 1869. William Preston died in Louisville and was interred in
Cave Hill Cemetery in Louisville. ==See also==