Wiktionary
n. An international conflict by military, diplomatic and/or other means between monarchies, in which the dynastic interests are a major consideration, notably determining if states ruled by such dynasties will be united or broken up
Usage examples of "dynastic war".
It surely would have become an Eighth Dynastic war, except for the arrival of the foolish Utara.
He found himself watching a depiction of the epic Fourth Dynastic War which pitted the Northern and Eastern United Clans of ancient Quozlene against the Southern.
Of those, three had been broken in dynastic war, shattered in the hands of dying kings and queens.
Gustav VI had been a childless only son, but he'd had half a dozen male cousins, and a nasty dynastic war had been in the making until the oldest of his three sisters put an end to the foolishness by embracing a legal fiction.