Use of the Jolly Roger by submarines

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.

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.

[4][6] The flotilla leader wanted to recognise the boat's achievement, which had involved penetrating deep into the heavily guarded Adriatic, so had a Jolly Roger made and delivered to Osiris.

HMS Conqueror raised the flag to recognise her successful attack on the Argentine cruiser ARA General Belgrano during the Falklands War.

During World War II, Allied submariners working with Royal Navy fleets adopted the process from their British counterparts.

Following the first Australian live firing of a Mark 48 torpedo in 1987, HMAS Ovens used the flag to indicate the successful sinking of the target ship Colac.

[19] At least twice in 2017, the USS Jimmy Carter, a U.S. Navy attack submarine which has been modified to support special forces operations, returned to its home port flying a Jolly Roger.