Allow me to quote from Jim McGhee's recently published "Guide to Missouri Confederate Units, 1861-1865" about this very issue of the 4th Infantry Regiment on page 201. Earlier on that page McGhee wrote that this regiment was part of the 1st Missouri Brigade that served in Mississippi and was in the Vicksburg siege. McGhee also wrote:

"Approximately 180 soldiers deserted the regiment, primarily after the surrender of Vicksburg [July 4], and many of them saw service thereafter in Trans-Mississippi units."

I could find nothing special at home near Oregon, Shannon, Carter, and Reynolds County that would compel these men to desert any more than any other event at that time. Evidently, they deserted because of the great Confederate loss in which they were involved on 4 July 1863.

By the way, McGhee says that:
--Company B was mostly from Howell County and commanded by William Howard, who was dropped from the rolls 12 June 1862, and thereafter by Daniel W. Nicks;
--Company D was mostly from Oregon County and commanded by J. Posey Woodside, who was disabled by wounds 4 Oct 1862, although McGhee could not name his replacement as captain of this company;
--and Company I was mostly from Oregon and Reynolds Counties and commanded first by William A. Farris, who was dropped from the rolls 15 June 1862, and thereafter by Matthew G. Norman.

Bruce Nichols