The sea has always been a metaphor for freedom – an escape from governments, laws and much else. My reporting had long focused on those who take advantage of that to murder, enslave, dump and steal. But the romance, wilderness and lawlessness of that frontier has also inspired mavericks, renegades and visionaries, an array of swashbuckling characters who used the murky laws of the high seas to dream up alternative world orders, utopian safe havens.

Sealand is a perfect example: a ‘micronation’ consisting of an eerie metal platform atop a concrete base that is located a few miles off the coast of England in the North Sea. In 1965, the BBC and other broadcasters were only playing popular music late at night, leaving young audiences starved for more. Rogue DJs turned to the outlaw ocean. Aboard ships in the rough North Sea just beyond the reach of British laws, pirate radio stations were born and quickly attracted millions of listeners. One such pirate broadcaster was Patty Roy Bates, who took this legal quirk a step further.

On Christmas Eve of 1966, he motored a small boat seven miles off the coast of England to a rusty, abandoned anti-aircraft tower. Built in the early 1940s as one of five forts that defended the Thames, the place was little more than a wide deck about the size of two tennis courts set atop two hollow, concrete towers, 60 feet above the ocean. At the time, Roughs Tower lay just outside British waters. Inspired with a nutty idea for a perfect gift for his wife Joan, Roy took hold of a grappling hook and rope, clambered aboard, and declared it conquered, even making it into the local news at the time.

He named the disused platform just outside Britain’s territorial waters Sealand. It didn’t look like much, but now it was his and his alone, and what a perfect gift for his wife. It wasn’t long before Bates’ new nation was challenged in British courts, a colourful story that was reported by the media at the time. The British Navy sent a boat close by and Roy Bates’ son, Michael, fired warning shots. Father and son were brought to court, but a judge ruled that since Sealand lay seven nautical miles outside British waters, British courts had no jurisdiction.

Bates took that as recognition. The motto of the country over which he now reigned was ‘E Mare, Libertas’, or ‘From the sea, freedom’. Constituted as a principality, Sealand had its own passport, coat of arms, and flag – red and black, with a white diagonal stripe. Its currency was the Sealand dollar, bearing Joan’s image.

Since Jules Verne’s Twenty Thousand Leagues Under the Sea was published in 1870, people have dreamed of creating permanent colonies on or under the ocean and reinventing to their advantage the laws that govern. Today, the movement to reconquer the ocean has received a new boost from Silicon Valley and Bitcoin investors. An organisation called The Seasteading Institute envisions water worlds where governments are selected in an open market, taxes can be waived, and climate change can be hacked.

Named after the homesteads of the American West, seasteads are conceived as self-sufficient, self-governing, part-libertarian utopia, part-billionaire’s playground. In the meanwhile, climate change and rising seas suggest their pioneering and sustainable housing and food production may just offer some solutions.

For all these lofty dreams of building brave new worlds in the outlaw ocean, the principality of Sealand, half a century old, remains the only ‘micronation’ standing in open waters to this day. Taking advantage of a gap in international law, Sealand has grown old while other attempts at seasteads never made it far beyond what-if imaginings. But the question for me is whether these creations will become island nations or remain island notions?

Perhaps the true secret to Sealand’s survival has been its limited aspirations. It had no territorial ambitions. It wasn’t seeking to create a grand caliphate. In the view of its powerful neighbours, Sealand was merely a rusty kingdom, easier to ignore than to eradicate.