In 1972, civil war broke out in Britannica, with the country then splitting into five smaller nations. The latest instalment in the troubled history of this imaginary realm has just been played out off the coast of Scotland.
HMS Albion was the command ship of the amphibious task group
Brownia, Mustardia, Cyanica, Ginger and Emeraldia have endured 35 years of conflict.
However, this strange parallel universe is not a work of science fiction but the scenario for Royal Navy exercise Neptune Warrior.
Last week 25 ships from eight different countries defended the people of Mustardia from terrorists and from Brownian attacks.
They were divided into two task groups - one headed by assault ship HMS Albion, the other by aircraft carrier and flagship HMS Illustrious. Albion practised putting Royal Marines ashore in simulated terror raids while Illustrious sent Harriers in to provide air cover.
The exercise was a key part of the ships' and marines' training before they are sent around the world to Afghanistan, the Gulf, the Caribbean, and Mediterranean. This meant the organisers at the Joint Maritime Operational Training Staff (JMOTS) had to simulate as many of the dangers found in these environments as possible.
"We sit down with all the commanders involved and look at the current geo-political situation," said Captain Paddy McAlpine, the commander in charge of running the exercise.
"At the moment we incorporate counter-terrorism, drugs raids, and gun-running as well as mine warfare and submarines, all set against an unstable political backdrop.
"It's got to be a complex scenario because the world we operate in is complex."
The changing face
The shape of the training has shifted over the years. It started after the Second World War as a way of getting the Royal Navy and RAF to work together to counter submarine attacks.
Through the Cold War the submarine threat was played out in a Cyanica v Mustardia (blue v red) scenario - one side a stable democracy, the other a communist dictatorship. Big navy took on big navy in a life-size "battleships" game.
But since the late 80s the exercise has had to adapt to the very different demands of a war in the Balkans and ongoing operations in the Gulf and Afghanistan.
In 2003, the fundamentalist terror group an-Quaich was introduced in direct response to the rise of al-Qaeda.
Royal Navy ships lined up with US destroyers to fire on Cape Wrath
The most noticeable feature of this year's maritime exercise was that all the ships were on the same side. The Mustardian navy worked like a Nato task force sent to provide humanitarian relief and reassure the local population while defending itself against terrorists.
HMS Ark Royal was working as part of an amphibious group led by HMS Albion, given the task of putting Royal Marines ashore to attack terrorist training camps. They were protected by a ring of ships, including American ships USS Laboon and USS Bainbridge. Working with Americans has become a key part of pre-deployment training.
"Bringing all of those assets together in one place really gives us a good work out," said the head of Ark Royal's Air Department, Commander Keith Muir.
The main challenge of bringing different countries' forces together was getting them to communicate quickly and effectively.
The biggest threat to the fleet came from an-Quaich terrorist attacks. These came in many different forms. Land forces were ambushed, ships were attacked by small fishing boats and light aircraft.
The difficulty for the men and women on the front line was identifying who were the terrorists and who were fishermen or even airborne journalists.
As the forces trained to avoid friendly fire attacks and civilian casualties, they had to operate within strict rules of engagement.
"It puts the commanders in a situation where they want rules of engagement that will allow them to shoot down threats to their ship," said Capt McAlpine.
"But what seems to be a threat might turn out to be friendly or neutral. There can never be a free-for-all fight."
Such difficult decisions are made even more challenging by the round-the-clock presence of "exercise media".
A team of more than 20 reporters, made up of working journalists and students, was sent round the fleet and air bases to thrust people of all ranks into the spotlight.
Despite recent criticism of the Royal Navy's handling of the media over the capture of HMS Cornwall sailors and marines, it goes to great efforts to create a realistic media presence.
A daily television news bulletin and selection of print stories is fed round the forces, commanders are asked to justify decisions on camera and press briefings are held to keep the media up to date.
"If an event happens then the media will know," said Capt McAlpine.
"We can't wait like we used to until we get into harbour to tell the press what's happened. We have to incorporate the media into what we do."