The 9.2-inch BL gun came into service in 1881 as an answer the the Krupp 24cm gun. The 10-inch BL gun, which was seen at that time as an alternative, came into service a few years later.
The Mark I and II of the 9.2-inch did not enter service, but the subsequent Marks followed over the next decade as the gun was steadily improved. One of the major improvements was the continuous motion breech loading mechanism as a replacement for the original three motion breech. The Mark IV and Mark V were the most commonly used in coastal defence batteries, with a preference for high angle mounts that allowed for plunging fire to come down on the decks of hostile warships.
The Mark IX and Mark X gun were introduced into service in 1899, the Mark IX being designed specifically for coast artillery batteries. The 9.2-inch BL gun became the standard heavy counter bombardment gun for British Coast Defence Batteries, working alongside the 6-inch Mark VII BL gun.