Cosmopolitan Arms Co. or Gwyn & Campbell Co. produced carbines in Hamilton during the Civil War, as described by Thomas B. Rentschler's book, Cosmopolitan and Gwyn & Campbell Carbines in the Civil War. Rentschler clarifies that there were two carbines -- the Cosmopolitan and the Gwyn & Campbell -- not two names for same weapon. They "are generally considered to be the only contract arms made for Civil War use west of the Appalachians," he wrote. Edward Gwyn and Abner Caruthers Campbell were partners in the firearms business that supplied carbines to the Union cavalry. Campbell, born in Hamilton in 1824, was a brother of Lewis D. Campbell and an uncle of Gov. James E. Campbell, prominent men in Butler County history and also Civil War veterans. Gwyn, born in London, England, in 1816, arrived in Hamilton in 1855 to operate the Hamilton Gas Light and Coke Co. that provided gas lighting in the town. Gwyn and Campell were partners in the gas works before teaming to produce weapons in 1859. The Civil War brought many changes to the cavalry. When the conflict started in 1861, mounted units relied on the hand gun -- usually a revolver -- and the sword. As the war progressed and technology improved, the cavalry switched to shoulder weapons, especially the carbine. A dramatic example of the transition came in 1863 with an offensive called Grierson's Raid. During that successful sweep into Mississippi in April and May of that year, the Hamilton-made carbines were in the hands of the Illinois troopers who did much to dispel the myth that only Confederates could be effective cavalrymen.
Colonel Benjamin H. Grierson, 37, commanded the expedition. "In 1861, well before his assignment to raid in Mississippi," Rentschler explains,
"Grierson's Sixth Illinois Cavalry was without adequate carbines, and he initiated an effort to find some. After correspondence and personal visits by Grierson to Hamilton, Ohio, and Gwyn to Washington, the federal government issued a contract to Cosmopolitan Arms Co. for 1,140 carbines on Dec. 31, 1861, with specific instructions that the carbines were to be shipped to Governor Yates [of Illinois] as he had requested." Starting April 17, 1863, Grierson's raiders confiscated more than 1,000 horses and captured or destroyed 3,000 arms during their 16-day, 600-mile campaign from LaGrange, Tenn., 40 miles east of Memphis, to Baton Rouge, La. The 1,700-man force also destroyed more than 25 freight cars, several locomotives, more than 50 miles of track and about 60 miles of telegraph lines. Grierson's Raid -- the most successful and most widely-acclaimed Union cavalry mission up to that time -- emphasized to army leaders the potential of well-planned, well-provided mounted expeditions. From 1859 to 1861, the firm operated in a small shop on the south side of High Street, opposite North Sixth Street. Gwyn and Campbell, Hamilton's largest employer during the Civil War, moved into an old cotton mill at the southwest corner of North Fifth and Vine streets. The company moved again in 1863 to the north side of High Street between Fourth (now Dr. Martin Luther King Jr. Blvd.) and Fifth (now Witt Way) streets. (Also see Long & Allstatter Co.)