In the history of naval warfare probably no type of ship has provided more firepower per ton than the monitor – indeed they were little more than a huge gun mounting fitted on a simple, self-propelled raft. Designed and built rapidly to fulfil an urgent need for heavy shore-bombardment during World War I, they were top secret in conception, and largely forgotten when the short-lived requirement was over. Nevertheless, they were important ships, which played a significant role in many Great War campaigns and drove many of the advances in long-range gunnery later applied to the battle fleet. Indeed, their value was rediscovered during the Second World War when a final class was built.
