William Anderson Pile (February 11, 1829 – July 7, 1889) was a nineteenth-century politician and minister from Missouri, as well as a general in the Union Army during the American Civil War.

At the outbreak of the Civil War, he entered the Union Army as chaplain of the 1st Missouri Light Artillery Regiment in 1861, serving under Colonel Clinton B. Fisk.

He was made captain, Battery I, 1st Missouri Light Artillery, March 1, 1862 and promoted to lieutenant colonel of the 33rd Missouri Volunteer Infantry September 5, 1862, and colonel December 23, 1862, brigadier general of volunteers in 1863, commanding Post of Port Hudson, District of Baton Rouge and Port Hudson, Department of the Gulf (December 26, 1864 - February 13, 1865; and commanding 1st Brigade, 1st Division, United States Colored Troops, District of West Florida, Department of the Gulf (February 19 - April 25, 1865, and brevet major general in 1865.

Named a brigadier general, he took up recruiting duties in St. Louis and was not particularly concerned to whom-loyal or secessionist-the slaves he inducted belonged.

[1] Pile was elected a Republican to the United States House of Representatives from Missouri in 1866, serving from 1867 to 1869, being unsuccessful for reelection in 1868.