Paddy Roy Bates, who occupied an abandoned fort in the North Sea and declared it the sovereign Principality of Sealand with himself as its prince, has died aged 91, his son said on Wednesday.
Michael Bates said his father died on Tuesday at a care home in Leigh-on-Sea, Essex. He had been suffering from Alzheimer's.
In the 1960s, inspired by the "pirate radio" movement, Bates set up Radio Essex on an offshore fort. When that was closed down, he moved in 1966 to Fort Roughs, a disused second world war platform in international waters about seven miles off the coast.
Michael Bates said his father initially intended to set up another radio station, but then "had the bizarre idea of declaring independence".
Rejecting a British order to leave, he proclaimed the fort the Principality of Sealand, declaring himself Prince Roy and his wife, Joan, as princess.
The 550-square-metre (5,920-square-foot) fort two concrete towers connected by an iron platform claimed to be the world's smallest sovereign state, though it was not internationally recognized.
Since an initial attempt to reclaim the fort was rejected by an English court, Britain has largely ignored the breakaway platform.
Despite the lack of legal status, Bates gave Sealand its own constitution, red, white and black flag, passports, stamps, coins, national anthem and a motto, E Mare Libertas: "From the sea, freedom".
Today, Sealand makes money by selling aristocratic titles and hosting Internet servers.
Lots of days I feel like finding an off sea platform and declaring my independence from this fake democracy we have here called Bloomberg LP, er, I mean New York City.
RIP Paddy Roy Bates.