The 12-pdr rifle was designed in the early 1850s by British manufacturer Joseph Whitworth, who had recently been contracted to improve the Pattern 1853 Enfield.

[1] Along with Whitworth's smaller 3-pdr gun, the artillery piece was considered for adoption by the British government's Board of Ordnance.

[1] During the American Civil War the weapon was exported and saw service in the Union and Confederate armies, though it was considered a rarity.

Like all of Whitworth's designs, the weapon had a distinctive hexagon-ally rifled barrel and was a breechloader (though it could be loaded via the muzzle with modifications).

[1] The cannon was forged using a method in which iron plates would be overlapped and forced together using hydraulic presses.