Were there other countries in history that claimed to be both

>>3217844

Constitutional Monarchies such as Great Britain are one. If you mean a system in which the monarch was elected, you're looking at the HRE in which princes voted for the new Emperor

>>3217847
>UK
Well, even though it is a democratic state, there is a republicanic movement in the UK that seeks to end the monarchy. PLC was oficially called the Republic of Poland (or of both nations), while maintaining the Kingdom of Poland and Grand Duchy of Lithuania as its subdivisions.

I am also not looking for countries that are elective monarchies (like HRE, like Vatican, like Malaysia and like Poland before 1569), but a state that calls itself a republic and the head of state is a monarch. I can even find examples of kingdoms in which head of state wasn't a king (interwar Hungary and Francoist Spain), but not the other way around.