Use of the Jolly Roger by submarines

The Jolly Roger is a symbol that has been used by submarines, primarily those of the Royal Navy Submarine Service and its predecessors. The practice came about during World War I: remembering comments by First Sea Lord Admiral Sir Arthur Wilson, who complained that submarines were "underhanded, unfair, and damned un-English" and that personnel should be hanged as pirates, Lieutenant Commander Max Horton began flying the flag after returning from successful patrols. Initially, Horton's submarine HMS E9 flew an additional flag after each successful patrol, but when there was no room for more, the practice was changed to a single large flag, onto which symbols indicating the submarine's achievements were sewn.

The practice of flying the Jolly Roger was adopted by some other submarines during World War I, but became more widespread in World War II. Flotilla commanders began to issue flags to submarines, and procedures were drafted for usage. Although some sources report the use of the flag being a universal practice among British submariners, some submarine captains did not take it up as the felt the practice was boastful and the achievements could not always be confirmed. Usage of the Jolly Roger was copied by some Allied submarines during World War II, and the flag has also been used by submarines from other Commonwealth nations.

The symbols on a Jolly Roger are used to indicate the achievements of the submarine. Bars represented ships torpedoed, although post-war flags have sometimes used the silhouette of the target ship instead. Mines indicated minelaying operations, while torches or lighthouses meant the boat had been used as a navigation marker for an operation. More unusual symbols have also been used, with comic character Eugene the Jeep marking the recovery of a Chariot manned torpedo, and a dog used for submarines involved in Operation Husky. Some icons are unique to a submarine: HMS Sibyl bears a scarlet pimpernel flower, marking the time a French spy forgot the recognition password and instead quoted from the play The Scarlet Pimpernel to prove herself, while a stork and baby was added to the Jolly Roger of HMS United when news of the birth of the captain's first child arrived while on patrol.

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