Royal Navy Armed Merchant Cruisers

At the very beginning of World War I British passenger liners were requisitioned by the Royal Navy for conversion to armed merchant cruisers in part to form the 10th Cruiser Squadron and also to relieve the strain on the regular cruisers by undertakinglone patrols, and later, convoy escort duties. Initially it was decided to also include the large ocean liners such as the Aquitania and the Mauretania but it was found that their very large size precluded them from the practical employment as A.M.C.'s. The logistics involved in their large fuel consumption and in providing suitable ports for refuelling and resupplying was very limited. As well, their large silhouettes made them identifiable from long distances. The Mauretania although converted and armed was never commissioned as an A.M.C. while the Aquitania was only commissioned for two weeks, ending after she collided with the steamer Canadian on 22 August, 1914.

Also on the acquisitions list but never converted were the liners Olympic and the Lusitania although both had been reinforced during construction to accommodate armaments in the event of war. The A.M.C.s were prominent in news reports with individual duals with their German counterparts as well as being part of squadrons throughout the world, such as at Coronel, the Falklands, and the Dardanelles. That they were largely unsuited in their role as warships is proven by the quick demise of the German A.M.C.s, proving highly vulnerable to hits due to a lack of any armour and they were gradually assigned to other duties as the war progressed. During the war seventeen of these were sunk, mainly from enemy action. As well as A.M.C.s, in 1917, fourteen others were fitted with anti-submarine weapons and classified as Escort Merchant Vessels, of which three were lost.

The most prominent employment of A.M.C.s was in the creation of the 10th Cruiser Squadron, used to maintain the blockade of the North Sea, its patrol area extending from the Norwegian coast far into the Atlantic and covering all approaches to the European continent from a northerly direction. In so doing they relieved twenty or more regular Navy cruisers for other duties. Forty-one different converted passenger ships served with the Squadron for some length of time, each armed with guns up to 6-inch calibre. The 10th Cruiser Squadron was finally paid off on 7th December, 1917.

Source: Liners In Battledress by David Williams - Vanwell Publishing Ltd. c-1989.

Ships of the 10th Cruiser Squadron:

Auxiliary Cruisers WWI ( first date is commissioning and second is date of return to owners or loss ) :

Escort Merchant Ships WWI :