Walter Reinhardt Sombre is a mysterious figure (he's variously thought to be German, French, Austrian, Swiss or Luxemburg-ish). He kicked around India in the 1750s-60s, changing sides constantly before entering the service of the Nawab of Bengal and slaughtering British civilians at Patna. He then fled justice and was made ruler of Sardhana by the Mughal Emperor. After his death his nautch girl wife ruled Sardhana for six decades.
The Clunies-Ross family settled the uninhabited Cocos/Keeling Islands with Malaysian workers and called themselves kings for five generations before the Australian government decided that the feudal regime was unattractive and forcibly bought them out in the 1970s. The last crown prince now catches clams or somesuch.