The name of the flag Jolly Roger is thought to have come from the French phrase 'joli rouge' meaning 'pretty red'. This flag was flown by HMS Safari in World War Two (Picture: PA).
The practice of Royal Navy submarines flying the Jolly Roger is at the centre of a new exhibition dedicated to the pirate flag.
The National Museum of the Royal Navy has put on display a selection of the flags including one seized from a pirate ship in the 1790s.
The original skull and crossbones flag was not coloured black and white as is commonly thought but was actually blood red to signify that no mercy would be given once the pirates boarded a ship.
The skull and cross bones came from the symbol used in ships' logs, where it represented death onboard.
But it was not only pirate ships that have flown the Jolly Roger - Royal Navy submarines adopted the practice since the First World War after a critic likened their crew to pirates.
On display at the exhibition at Portsmouth Historic Dockyard is a Jolly Roger flown by the Second World War submarine HMS Safari.
Each action a submarine carried out had its own symbol which was sewn on to the flag and was sometimes painted over to make it weather proof.
Victoria Ingles, senior curator at The National Museum of the Royal Navy said:
"These flags are a unique visual record of a boat's combat activities as well as a striking piece of folk art.
"The iconic Jolly Roger has become associated with the representation of pirates as swashbuckling rogues, cool rebels and fun children's characters but this exhibition exposes the dark side behind these stereotypical images.
"In reality, pirates commit brutal acts of violence and disrupt trade, which is why the Royal Navy still actively seeks to suppress their activities.
"Yet, despite fighting piracy, the practice of flying a Jolly Roger has also become tradition within the submarine service in response to a critic who likened them to pirates.
"Handcrafted, they are as much a symbol of pride and also poignant reminder of the impact of war."
The role of the Royal Navy in combating piracy is chronicled in the exhibition from the Jolly Roger belonging to Admiral Richard Curry which was seized at the end of the 18th century up to modern-day efforts.
The display starts on April 6 and is being held alongside a Horrible Histories Pirates exhibition.