The answer to this question is the Amenities Ship, a concept developed by the Royal Navy in the 1930s. The amenities ship had aboard it everything needed for a good period of rest and relaxation. They could be moved to wherever the fleet was based, whichever empty atoll or deserted island anchorage, and provide the sailors with a place to relax. With construction of warships constrained by the various naval treaties, the major navies of the world turned to amenities ships as a way to display their power and wealth.

As mentioned above, the Royal Navy was the first to develop the concept. They had gained significant experience of operating from remote, empty harbours during WWI, with the Grand Fleet based at Scapa Flow in the Orkney Islands. While Scapa was an excellent anchorage, and well supplied with munitions, fuel and other naval supplies, there was little to do there to relax. Nearly every naval memoir from the war describes the experience of Scapa Flow as being utterly tedious. It's no surprise that this experience influenced Captain Arnold A.F.M Keane, who had spent three years at Scapa, to write a paper describing the amenities ship concept in 1932. While little notice was taken of the paper at first, the RN soon seized on it. Plans were put in place for the construction of three amenities ships, built on the hulls of liners cancelled during the Great Depression. One would be based in the Far East, one in the Mediterranean, and one in Scapa Flow. The two for foreign service, Lycaon and Tantalus, were supplied with everything needed to support a fleet's worth of bored sailors. They had a cinema, kept well-stocked with all the latest movies, a large NAAFI canteen capable of dispensing sixty thousand gallons of tea and twelve tons of buttered crumpets in a day, and their own breweries, producing hundreds of bottles a day. The third ship, Midas, meanwhile, was much more luxurious, as she was built for the officers of Home Fleet; interwar improvements at Scapa had greatly improved the recreation facilities there, but they were still viewed as far too spartan for RN officers. Midas was lavishly decorated, had a theatre, rather than a cinema, a high-quality restaurant (during WWII, staffed with chefs taken from the Free French Forces), and a gin distillery. However, she would lose much of her finery during the war, as it was considered too easy a target for German bombers. The three ships proved their worth during the war, though Tantalus was sunk during the Japanese Indian Ocean raid in 1942. As the RN pushed back into the Pacific in 1944-5, two more ships were converted to a similar design, Agamemnon and Menesthus, and they served with distinction during with the British Pacific Fleet.

The IJN, with it's traditional close ties to the Royal Navy, was another early adopter of the amenities ship. With a strong desire to prove their strength compared to the Western navies, and with their abilities to do so limited strongly by the Washington Naval Treaty, they found the amenities ship a great avenue to do so. They began converting the liner Kobayashi Maru in 1937, to support the fleet in its anchorages at Truk and Babeldoab. She had the almost obligatory cinema, a pachinko arcade, as well as her own sushi canteen. This was fed by an early variant of the modern sushi conveyor belt. It was reasonably successful, though jams were common, preventing it making the leap to civilian use until after WWII. Kobayashi Maru was inspected by a number of RN officers, who were impressed by her comfort and design, though they preferred the RN's designs. She served mainly at Truk during the war, but was sunk nearly 75 years ago by the American submarine Aprilfish. The IJN did not complete another amenities ship, but work was well underway on a second in 1945. This was built on the unfinished hull of the fourth Yamato-class battleship, Echizen. While her half-sister Shinano was intended to maintain the air wings of the IJN's carriers, Echizen was intended to support their crews. Little information is present on her intended equipment, but it is believed she would have had been equipped much like Kobayashi Maru, as well as a swimming bath based on a traditional onsen.

The USN preferred to spend its money on more traditional auxiliaries in the 1930s, but also completed a single amenities ship in the period, the USS Hollywood, completed in 1938. Unlike the RN and IJN, the USN was 'dry', so Hollywood did not serve alcohol. Instead, she was given a soda fountain, often proclaimed to have the 'longest counter in the world'. She had vast tanks for carrying soda syrups, with capacity of at least 10,000 gallons in four different flavours, as well as a carbonation plant. Unfortunately, she had little chance to serve any sailors in anger, being sunk by U-269 off the North Carolina coast as she was travelling to join the Pacific Fleet in January 1942. Her sinking was somewhat surreal as the torpedo hit opened her syrup tanks, leading to what one survivor described as "the sweetest shipwreck I ever tasted". Still, pre-war exercises with her had shown the USN the value of the concept. Tens of Liberty Ships were converted to amenities ships to support the USN advances across the Pacific. The fleet base at Noumea, supporting the invasion of Guadalcanal in 1942, had "one ice-cream ship, one soda ship, two cinema ships and one restaurant ship", in addition to the more warlike oilers and ammunition ships. Three years later, and the force providing recreation for the fleet for the invasion of Okinawa had grown tenfold. Pride of place amongst these was taken by the two Wrigley Field class ships, Wrigley Field and Lambeau Field. Converted from unwanted Independence-class carriers, they were essentially giant floating sports centres. The flight decks were covered in turf, and kitted out for baseball (Wrigley Field) and American football (Lambeau Field), while the hangar decks were converted to basketball courts, or squash and tennis courts. Their aviation petrol tanks were knocked through, and converted to a swimming pool. They had sufficient capacity to allow for the entire crew of a Baltimore-class cruiser to be exercising at any one time. They were highly popular, though not so much with the USN's allies, as Lieutenant J. Smith of the British destroyer HMS Nonsuch described in his diary:

20th March 1945: Nonsuch met the American Fleet Train for replenishment and rearmament. I took a party of men aboard one of the big American sports vessels we've heard so much about in the newsreels. High Command had informed us that we were being provided with a ship outfitted for football, so the men were very much dismayed to find that the goalposts and pitch markings were for the inferior American game, rather than for what they call 'soccer'. Still, the British tar can find enjoyment anywhere, and a game was soon going, using caps 'borrowed' from our American hosts for goalposts.

Another sports vessel, albeit one that never got off the drawing board, was a Canadian project based on Project Habbakuk, the plan to construct a giant aircraft carrier out of 'pykrete', an ice/sawdust mixture. The RCN soon realised that this would also make a perfect playing surface for ice hockey. A plan soon formed for a floating ice island, with no less than twenty hockey rinks, to be placed in the North Atlantic to support convoy escorts. Ships could dock, refuel, send their crews aboard to rest and relax, before heading back out to join the battle. Churchill was much in favour, apparently because aboard it would be the only place he'd be able to get a properly cold martini, but it was soon superseded by developments in the Atlantic.

The European navies, with limited need to operate from distant harbours, never really got into the amenities ship game, but there were two projects worth mentioning. The first was the French wine tanker Bourgogne. Designed to support a fleet in the tropical waters of French Indochina, she was equipped with an innovative evaporative cooling system capable of keeping her supply of 500,000 litres of wine at a perfect temperature, no matter how hot it got outside. While she was completed, she never served, and was scuttled at Toulon along with the rest of the Vichy Fleet. The other is the German Rücksichtslos latrine ship. Following the Fall of France, the Kriegsmarine began establishing submarine bases on the western coast of France, as well as in the Norwegian fjords. It was soon discovered that while these bases had plenty of storage for food, fuel and torpedoes, the toilet facilities were lacking. To solve this problem, the Kriegsmarine began constructing a flotilla of latrine ships, capable of providing the U-boat fleet with toilets wherever they were based. Rücksichtslos was the only ship completed before the steel for the fleet was diverted to constructing tanks and V-2 rockets. She had a quite astonishing range of facilities, from latrine troughs capable of seating 40-50 enlisted men to individual suites with private showers, manicurists and massage tables for U-boat captains. She survived the war, and was surrendered to the Allies in 1945.

Sources:

Amenities Ships of WWII, Angus Konstam, Osprey, 2018

Rum, Sodomy and the Lash: Recreation in the Royal Navy 1914-45, George Field, Cassell, 2013

Miscellaneous Vessels of the Kriegsmarine, Volume 3: Oilers, Repair Ships and Latrine Ships, William Garzke, USNI, 1985

Floating Pleasure Palaces: Amenities Ships of WWII, Norman Friedman, USNI, 1978

Gravity's Rainbow, Thomas Pynchon, Viking, 1973

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