There's always more to be said on the topic, but u/JoshoBrouwers gave a great answer to this in In the Bronze Age Mediterranean, states such as Hattusa, Egypt, Assyria, et alia are described as unified, unitary monarchies. However, I have not seen any in-depth exploration of the government of the Mycenaeans. What sort of state(s) did they possess? What forms of government did they practice?