Captain Samuel H. Libby Mounted on Horseback, quarter-plate tintype, Napoleonville, Louisiana, c. 1864–1865.

Rare, historically significant outdoor quarter-plate tintype depicting Captain Samuel H. Libby of Company L, 2nd Maine Cavalry, seated atop his warhorse in the field at Napoleonville, Louisiana. Capt. Libby is pictured in full field dress wearing a slouch hat, officer's frock coat with prominent shoulder straps, riding boots, and gauntlets, with his cavalry saber visible at his side. Mounted outdoor portraits of Civil War cavalry officers taken in the Southern theater of operations are exceptionally rare, as most equestrian images were executed at northern training camps prior to deployment.

The 2nd Maine Cavalry mustered in late 1863 and served in the Department of the Gulf, seeing active reconnaissance, picket, and anti-guerrilla service in Louisiana and West Florida. Period ink identification inside the case housing explicitly places the image at Napoleonville, Louisiana, a strategic Union post in Assumption Parish along Bayou Lafourche. Mounted tintypes with contemporary field locations represent premier, highly sought-after acquisitions for 19th-century photography collectors.

Capt. Libby (1840–1871) was a native of Limerick in York County, Maine. He initially entered Union service as a First Lieutenant in Company A of the 9-month 27th Maine Volunteer Infantry, which mustered in late 1862. Following the expiration of the 27th Maine's term in mid-1863, Libby reenlisted when the 2nd Maine Cavalry was organized in Augusta between late 1863 and early 1864, receiving a commission as Captain of Troop L. He survived the War, but died shortly after its end. His legacy as a prominent local officer was honored in his hometown when the Grand Army of the Republic Post No. 133 in Limerick, Maine, was officially named the Samuel H. Libby Post in his memory in 1886.

Housed in a full leather case with an oval brass mat and ornate preserver. Preserved behind the image in the tray is a crisp, period pen-and-ink inscription reading: "Capt. S. H. Libby / Troop 'L' 2nd Me. Cav. / Napoleonville, La."

The plate exhibits outstanding clarity, rich tonal contrast, and crisp focus across both the officer and his mount, showing only light, harmless peripheral tarnish near the mat line.