What royalty is, what it does and how that state is passed on varies from country to country and changes with time. It can also vanish. The last King of Jaille is better known today by the sobriquet, “The Father of the Republic” than by his reign name of PhillippeVI.
The Terrencian Emperor is the inheritor of a martial, patrilineal tradition that claims descent from a tribal leader who, after the fall of Atlantis, parleyed control of iron and salt mines into control of a territory three times its original size. His professional descendants now control a good forty per cent of Europe plus various colonial outposts; the Terrencian Emperors have always been the kind of people who send an army after you if you doubt their origin story and they have always been heavily militarised. Power and inheritance traditionally flow through the male line, although the three Empresses Regnant have been among the most successful and the most celebrated rulers of the Empire. The Imperial and Royal family represent the State, and the Terrencian State has always been about military power as a means to an end, which is the underlying reason why Terrencian male royalty is usually in military uniform.
In northern Europe ‘King’ was originally an elected position, chosen from among candidates qualified by birth and achievement by those qualified to vote by social position, gender and acknowledged skill set. This changed slowly, kingdom by kingdom, so that by the late medieval period the crown in all these kingdoms passed by inheritance, predominantly in the male line. The main variation to this system lies in the eastern most of the Norse kingdoms where inheritance is by acknowledged heirs, not legitimate heirs (itself a concept that doesn’t exist in their legal structure.) It is probably relevant to note that as late as the beginning of the Steam Age the Russkiyan crown officially referred to this kingdom as a ”tribal state.”
Russkiyan royalty now exists only in exile. The last enthroned Grand Prince and Autocrat was executed, with all his immediate family, by the revolutionaries who founded the soviets. His authority over the people and the country had been religious as much as it was temporal and his death proved that the monarchy had been a foundation rock of the nation’s society – a century after his death, his people’s descendants are still trying to find their balance.