I'm going to venture a quess that he never reported with Hastings'/Hughes' company May 12, 1861 at Cornith when they entered Confederate service. That would explain the absence of his name on their rolls.
There is no record of him in the Confederate Rest section of the Vicksburg city cemetery. However, we still have some 1000 unknowns buried there.
George Martin
Milton Scott, age 24, mustered into service as a Private in Captain J. G. Hastings' Company (Claiborne Guards), Mississippi Volunteers** March 23, 1861 at Port Gibson [this muster roll was not signed], no other records
**This company was successively designated as Captain Hastings' Company and Captain Hughes' Company, Mississippi Volunteers, and as Captain Hughes' Company, (Old) Company H, and (New) Company K, 12th Regiment Mississippi Infantry.
The 12th Regiment Mississippi Infantry was organized in May, 1861, of companies which had previously been in the State service and was mustered into the Confederate service for twelve months.
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12th Regiment, Mississippi Infantry
12th Infantry Regiment was assembled at Corinth, Mississippi, in May, 1861. The men were from the counties of Hinds, Adams, Lawrence, Copiah, Warren, Panola, Claiborne, Yazoo, Jefferson, Holmes, and Calhoun. Ordered to Virginia, it was assigned to General Rodes', Featherston's, Posey's, and Harris' Brigade. The regiment participated in the various campaigns of the Army of Northern Virginia from Williamsburg to Cold Harbor, endured the hardships of the long Petersburg siege south of the James River, and saw action around Appomattox. It was mustered into Confederate service with 1,013 men and lost 41 killed and 152 wounded at Seven Pines. The unit sustained 225 casualties at Gaines' Mill and Grayser's Farm, 59 in the Maryland Campaign, and 64 at Chancellorsville. It took 305 effectives to Gettysburg and surrendered with 1 Assistant-Surgeon and 53 enlisted men. The field officers were Colonels Richard Griffith, Merry B. Harris, Henry Hughes, and William H. Taylor; Lieutenant Colonel Samuel B. Thomas; and Majors James R. Bell, John R. Dickins, and W.H. Lilly.