It appears that Captain Dunn's company was a part of the 5th Arkansas

The county was sparsely settled at the beginning of the war, but the sentiment of the people was almost unanimous in favor of the Southern case. The first company of soldiers to organize for the purpose of joining the Confederate ranks was commanded by Poindexter Dunn, as captain The second company was raised by Captain Fisk, the third by Captain J.M. McGee, and the fourth by Captain Frank M. Prewett, who still lives, and resides in Forrest City. He is also a Mexican War veteran, and though 77 years of age, is hale and hearty, and is highly esteemed by a large circle of friends. The fifth company was organized by Captain Paul M.Cobbs, afterward State Land Commissioner, who died in 1890. All of these companies did valiant service for the cause they espoused, and only 100 of the 600 who enlisted survived the war Jack Cheney, of Captain Cobb's company, was the first to mount the Federal breastworks at the battle of Helena. Forrest City Times-Forrest City, Arkansas:1905 Art Souvenir, page 25