In Sikakis, Stewart, Compendium of the Confederate Armies, Florida and Arkansas, Facts on File, Inc, ISBN 0-8160-2288-7, Page 126, it describes the break up of Williamson's Infantry Battalion, which it says was formed from eight companies of the 15th Militia Regiment. It says that the companies were broken out to other Confederate Commands as follows.

Companies A and B to 21st Arkansas Infantry Regiment,
Companies C and D to 1st (Brook's) Arkansas Cavalry Battlaion,
Companies E, F, and H to 3rd Arkansas Cavalry Regient
Company G to 31st Arkansas Infantry Regiment

I am primarily concerned with tracking what became of the pre-war militia companies and Volunteer companies. I am interested in any other specific information on Militia Companies enrolling in the new Volunteer Regiments.

Does anyone have information on other militia unit enlisting in mass in Volunteer Regiments?