18th Arkansas Infantry Regiment (Marmaduke's)  The 18th Arkansas Infantry (Marmaduke's) (1861–1865) was a Confederate Army infantry regiment during the American Civil War. The unit was also briefly identified as the 1st Arkansas Infantry Battalion. The unit was most often referred to as the 3rd Confederate Infantry Regiment. The designation "Confederate Infantry Regiment" was intended to convey the difference between Provisional Confederate Army units and Regular Confederate Army Units, with Provisional units being those regiments who received a state designation such as "XX Arkansas Infantry Regiment". In practice, the designation was most often utilized when Regiments were assembled utilizing companies from more than one confederate state. The "3rd Confederate Infantry Regiment" is occasionally misidentified as the 3rd Arkansas Infantry Regiment commanded by Colonel Van H. Manning. The 18th Arkansas Infantry started out as 7 of 22 companies which comprised the so-called "Hindman Legion." Col. Thomas C. Hindman had recruited ten companies at his own expense for the 2nd Arkansas Infantry Regiment, and then an additional seven companies at his own expense which, along with four cavalry companies and an artillery battery, became known as the Hindman Legion. The "Legion" was not approved as an organization, and, after being mustered into the Confederate service on July 27, 1861, reverted to a regiment (the 2nd Arkansas Infantry Regiment), an infantry battalion "(the 1st Arkansas Infantry Battalion)" and a cavalry battalion (the 6th Arkansas Cavalry Battalion). John S. Marmaduke was assigned as commander of the 1st Arkansas Infantry Battalion and promoted to lieutenant-colonel on August 1, 1861. A company from the 15th Tennessee Infantry was transferred to the 1st Arkansas Battalion, and two additional companies were added on December 18, 1861, which brought the battalion up to ten companies. On January 1, 1862, the unit was formally designated as a regiment, the 18th Arkansas Infantry, and Marmaduke was promoted to colonel. On January 31, 1862, the regiment was redesignated as the "3rd Confederate Infantry" because it contained units from multiple states. John S. Marmaduke was assigned as commander of the 1st Arkansas Battalion and promoted to lieutenant-colonel on August 1, 1861. A company from the 15th Tennessee Infantry was transferred to the 1st Arkansas Battalion, and two additional companies were added on December 18, 1861, which brought the battalion up to ten companies. On January 1, 1862, the unit was formally designated as a regiment—the 18th Arkansas Infantry—and Marmaduke was promoted to colonel.