Science fiction curiously includes a large number of High Kings and Galactic Emperors:
“Curiously” in the sense that (at any rate to ‘Murricans) it is a form of government associated with the past, and certainly not with rocket ships, monorails, food pills, cyborgs, or the rest of the retro-future paraphernalia that sci-fi still loosely connotes in the popular culture.
For my purpose, the virtues or defects of monarchism as a political position are fairly beside the point. Kingship has certainly been widespread, suggesting that it was a workable default position, at any rate in the agrarian age. For an intellectual defense you probably still can’t do better than Hobbes’ Leviathan. Not to mention that as a critique of anarchism and its cousins, it is hard to improve on solitary, poor, nasty, brutish, and short.
But I would argue — in fact, I will argue — that the roots of monarchism in SF have less to do with political philosophy than with basic story considerations.
Bourgeois representative democracy, classical Athenian-style democracy, classical Roman-style republicanism, medieval oligarchical republicanism a la Venice, military juntas, fascistic fuehrerprinzip, Leninist dictatorship of the proletariat, nominally Communist party-committee oligarchy, pure bureaucratic functionary-ism, and both Iranian and al-Queda style theocracy, all have at least one thing in common: The likelihood of a teenage girl becoming head of state under any of these systems is pretty much nil.
Or, to put it another way, hereditary monarchy is singularly well-suited to Romance. By fully entangling the personal and the political it provides great story fuel. And story trumps futurism, or even political philosophy, every time.
One of the commenters mentions the Dune Encyclopedia, which was written as if it existed in the fictional universe of the books:
It filtered all that was known about the present through a “Monarchist” filter. So World War II became a “minor trade dispute between House Tokyo and House Washington in the British Empire”.
Actually, here’s the original passage, featuring the Houses Washington, Nippon, and Windsor:
The practice of maintaining stockpiles of atomic weapons as an integral part of a House’s defenses began when primitive nuclear weapons were invented on Old Terra on the eve of the Little Diaspora, by the “Raw Mental,” Einstein, who was working for House Washington. When Einstein succeeded in his attempts to construct these weapons, two of the first were used to settle a trade dispute with House Nippon. These weapons were of such a primitive nature that fewer than a million casualties were caused by the explosions — but one must remember that the entire empire at this time had only three billion subjects, all on one planet. The demonstration, though unremarkable by later standards, served two purposes: the destruction of two small cities and the threat of the destruction of others forced House Nippon to concede the lucrative Pacific trade routes to House Washington; and possession of the Empire’s only atomic weapons gave House Washington the prestige and power it needed to displace House Windsor.