The title is misleading, but it’s basically this
Challenge: In different parts of the world, from Europe, to Africa, to the Middle East, to other Asian Counties, and to even America (Pre-Columbian or Post) Have prominent and influential Noble families of various, different kingdoms and Empires, become de facto rulers for their nations, and their House or Dynasty holding that title for generations (The title becoming hereditary) while being nominally appointed by their Monarch or head of state (who are just figureheads)
Challenge: In different parts of the world, from Europe, to Africa, to the Middle East, to other Asian Counties, and to even America (Pre-Columbian or Post) Have prominent and influential Noble families of various, different kingdoms and Empires, become de facto rulers for their nations, and their House or Dynasty holding that title for generations (The title becoming hereditary) while being nominally appointed by their Monarch or head of state (who are just figureheads)