Prince Leonard (real name Leonard George Casley) has presided over the Principality of Hutt River since announcing its secession in 1970 in protest at the government's agricultural policy. But the 91-year-old has now handed his position and ceremonial robes over to his son, Graeme.
Located 350 miles north of Perth, the Principality of Hutt River has become a popular tourist attraction, attracting up to 40,000 visitors each year. It is big - around 75 square kilometres - but has only 23 permanent residents. It issues its own commemorative coins, and even accepts company registrations (although the Australian Taxation Office has raised doubt as to their legality).
Located between the islands of Nevis and Montserrat, the tiny island of Redonda was - according to legend - claimed by Matthew Dowdy Shiell in 1865, who, by the alleged approval of the British Colonial Office, took with it the title of "King".
The title was then given to his son, the author Matthew Phipps Shiell, who claims he was crowned in 1880, at the age of 15, by a bishop from Antigua. There are currently at least four claimants to the throne, while in 2007 the Wellington Arms in Southampton tried to get around the smoking ban by declaring itself an embassy of Redonda.
The Principality of Sealand
This Second World War sea fort, seven miles off the Suffolk coast, was seized by pirate radio broadcaster Paddy Roy Bates in 1967. Bates sought to establish the platform as a sovereign state, and in 1968 a British court bolstered his claims by declaring it outside of British jurisdiction (Bates had been summoned by the law after firing warning shots at two workers who were attempting to service a navigational buoy nearby).
The 0.025 km fort has its own constitution, flag, national anthem, coat of arms, currency and passports, and even survived an audacious attempted German invasion in 1978. Bates died in 2012, and was succeeded as Prince of Sealand by his son, Michael.
In 1982, in an effort to curb drug smuggling, the US Border Patrol set up an inspection point on the road between the Florida Keys and the mainland, resulting in long traffic jams and a drop in visitors. The mayor of Key West, Dennis Wardlow, concluding that the roadblock was effectively a border station, did the only reasonable thing: he declared full-blown independence.
Continuing his protest, Wardlow declared war on the US, surrendered a minute later, and then applied for $1bn in foreign aid. The stunt helped shed light on the city's plight and the inspection point was shifted, but the name of the Conch Republic continues to be used for promotional purposes.
The Republic of Molossia
Conceived by Kevin Baugh in 1977, as part of a school project, and established in 1999, Molossia consists solely of Baugh's one-acre home in Nevada. Baugh (the president, naturally) describes it as a "dictatorial banana-republic" where martial law is in place "due to unrest and the ever-present foreign menace from over the border".
Molossia, while itself unrecognised, has numerous treaties with other micronations, and claims it was one of the first countries to recognise Kosovo. All of Baugh's efforts haven't gone unrewarded - his home attracts a modest number of tourists, with visits arranged on request.
The Republic of Užupis
Rather more inclusive than Kevin Baugh's one-home republic is the micronation found in the bohemian Užupis district of Vilnius, Lithuania. It was declared in 1997 and has its own constitution with articles including "A dog has the right to be a dog" and "People have the right to live by the River Vilneli, while the River Vilneli has the right to flow past people"; as well as "Man has the right to individuality".
It also has its own flag, (small) "army", and national anthem. Its projects are largely artistic and humourous.
Freetown Christiania
One of the larger examples on our list, Freetown Christiania - established in 1971 - is a neighbourhood of around 850 people within the Copenhagen district of Christianshavn. It is also among the most successful, and Danish authorities have granted it a unique legal status.
Its residents - like that of Užupis - are bohemian. Performing arts, yoga and meditation are all popular activities, cannabis is openly traded, and visitors (it is a popular detour for tourists) will spot eye-catching murals and unusual architecture.
Grand Duchy of Flandrensis
Founded by Niels Vermeersch, a Belgian, in 2008, Flandrensis claims five Antarctic islands (Siple Island, Cherry Island, Maher Island, Pranke Island and Carney Island) - based on its own interpretation of the Antarctic Treaty of 1959.
It has its own ID cards, currency, newspaper, constitution and national anthem, and boasts more than 100 citizens from 21 countries.
This defunct micronation was founded in 1948 by Russell Arundel, an American businessman and PepsiCo lobbyist, on Outer Bald Tusket Island, the southernmost of Nova Scotia's Tusket Islands. Arundel spotted the island while fishing and bought it for $750.
Legend has it that he and his friends conceived the idea of declaring independence during a particularly heavy rum-drinking session. The tongue-in-cheek state was largely nautical themed - its currency was called the Tunar, for example, while anyone who caught a bluefin tuna there acquired the title of prince. Arundel sold it to the Nova Scotia Bird Society in 1973.
The Kingdom of Lovely
Created by Danny Wallace for the BBC documentary How to Start Your Own Country, The Kingdom of Lovely is headquartered in his East London flat, and has its own flag, coat of arms, and motto ("Die dulci freure" - Have a nice day). Thanks to the internet, it managed to attract more than 50,000 "citizens".