This guy occupied an abandoned military structure located 6 miles off the coast of England in claimed it was a sovereign nation (which he named Sealand), and dubbed himself "Prince Roy". Sealand has even been involved in a war with England.
Never heard of Sealand? That's not a surprise. It's a concrete dot in the North Sea roughly the size of two tennis courts, and it's never been recognized by any other nation on Earth. But that never bothered its eccentric founder, Paddy Roy Bates.