The 4th Regiment, Mississippi Infantry (Confederate) was organized as early as April 1861 as the 4th Regiment, 2nd Battalion in Yalobusha County, Mississippi under the command of Col. Joseph Drake and served under the Western Theater under Tilghman's, Drake's, Lee's, Thomas', Baldwin’s, and Sears' Brigades in the Army of Mississippi. It was later commanded by Cols. Pierre S. Layton and Thomas N. Adair. (HMU, 13; DR-MSOR, 543-550; NPS-BU)
See also: https://books.google.com/books?id=BCYLAAAAMAAJ&printsec=frontcover&source=gbs_ge_summary_r&cad=0#v=onepage&q&f=false
The graph displays the other subjects mentioned on the same pages as the subject "Confederate States of America. Army. Mississippi. Infantry Regiment, 4th". If the same subject occurs on a page with "Confederate States of America. Army. Mississippi. Infantry Regiment, 4th" more than once, it appears closer to "Confederate States of America. Army. Mississippi. Infantry Regiment, 4th" on the graph, and is colored in a darker shade. The closer a subject is to the center, the more "related" the subjects are.