Wilson Sproul was born around 1842 in New Jersey to James and Julia Sproul. His father was a carpenter and farmer who owned $7,000 of real estate and $1,200 of personal property by 1860. He grew up and attended school in Raritan, New Jersey.
He enlisted in the Union army on September 29, 1861, in Brooklyn, New York, and mustered in as a private in Company C of the 87th New York Infantry on October 2. He took part in the siege of Yorktown, the Battle of Williamsburg, the Battle of Seven Pines, and the Second Battle of Bull Run. The army transferred him to Company C of the 40th New York Infantry on September 6, 1862, and he participated in the Battle of Antietam, the Battle of Fredericksburg, the Battle of Chancellorsville, the Battle of Gettysburg, the Overland Campaign, and the siege of Petersburg.
He was absent without leave in the fall of 1863, but he eventually rejoined his regiment. He remained devoted to the Union. In August 1864, he hoped that the "United States or the Northern States [would] unite as one main body and try to whip out this stain that is upon our banners...we must hope all for the best and do all in our power to suppress them, witch I believe will be done if it takes three more or six years to do it in."
He mustered out on October 6, 1864, when his term of enlistment expired. He returned to his parents’ household in Raritan after the war, and he remained there until at least 1880. He earned a living working in a sawmill. He applied for a federal pension in January 1900 and eventually secured one. He died on November 4, 1904.