This rare Ohio state sword belt plate is a thing of beauty as well as an artifact of the Civil War period. In the years leading up to the Civil War there was an enthusiasm for volunteer militia companies. These units were equipped with arms from an allowance provided each state by the Federal government, but all other items were the responsibility of the members. Since these were state formations the motif on their buttons, buckles and insignia often reflected their state of origin. It this case we see the seal of the state of Ohio. In some cases these would have been available as stock items from military outfitters and in others they would have been special ordered. The Ohio state seal reflects that adopted in 1847. More modern versions of the seal omit the camel-back riverboat.
The officers of state militia units were men of position and wealth in their communities and spared no expense with their uniform or equipment. Many of these same men were also commissioned in the state volunteer regiments that were mustered into federal service during the Civil War and were the backbone of the Army. There was no reason that they could not continue to wear uniforms and equipment with state motifs, such as this belt plate. Many such state items, particularly buttons that were used both by officers and enlisted men, are recovered from Civil War sites. It is also possible that the officer who wore this plate had never seen service in the prewar Ohio militia, but wished a sword belt plate reflecting his state of origin. Officers' uniforms and equipment were privately purchased not issued and this gave them some freedom with respect to features of the uniform.
Reference:Binder, Daniel J., "A Rare Civil War Period Ohio Militia Officer's Sword Belt Plate", Military Collector and Historian, LVII (3): 141-142 Fall 2005.