The followers of the mechanogod Whrrrm, those who could never have come about until the advent of steamtech.
And because they had shown they could not be trusted, Iev abolished the use of Kren save by those few individuals he trusted.
~The True History of the Order, by F’ian circa 300 AW
A kingdom where, if there are multiple princes (princesses can't rule unless they have no siblings), the princes fight to the death in the arena to decide who gets to rule. A simple way to make sure your brother cannot make a bid for the thrown, and keeps the royal blood in one line.