This question has been asked before but received no valid answers. I am quite interested in the answer, though, so I hope I break no subreddit rules by asking this question again since the previous post is 11 months old.
Question: Did/does monarchy offer any advantages for pre-modern states over democracy? Did any ancient writers living in Republican Rome or in non-monarchic cities of Greece ever advocate for monarchy over democracy?
Edit: Thanks a lot for all the responses!
Monarchy is much older than democracy. Ancient Egypt, Sumer and China were all ruled by kings as early as the 3rd millenium BC. Democracy appears in classical antiquity and in case of both the Athenian democracy and Roman republic, it is established when the aristocracy deposed a tyrannical king.
If we're to discuss what's the advantage of either, you need to first ask the question 'advantage for whom'. Over 90% of the population for the biggest part of human history were poor farmers, who didn't really have much power either way. Power was usually held by some sort of aristocracy that held most of the land and did what it could to keep itself exclusive. Kingdom is pretty good for everyone if the king knows what he's doing and awful if a maniac or an idiot ascends to the throne. Democracies and republics are favored by aristocracy, but an oligarchic republic like republican Rome only worked while all members of the aristocracy were more or less equal and there was cohesion in the ranks.
What I'm trying to say is, a system of government that favors wealth and power being concentrated in the hands of a small amount of people is supported by the people that hold power, and the rest doesn't really enter the equation. For the biggest part of the population, it makes no difference whether they are ruled by an emperor or a tyrant, or a bunch of old rich windbags in the Senate. They favor peace and prices of food being reasonable.
If we're talking about things like stability or potential for expanding your territory or establishing commercial interests, I don't think it's possible to discuss in the context of monarchy vs democracy. Each kingdom and democracy was different in its own way.
Thucydides argued that although Athens was obviously a democracy, it was in effect presided over by Pericles, who was the strongest military general Athens had at it's disposal during the Peloponnesian War. In his own way, Pericles effectively governed Athens and helped forge the Athenian Empire, although he had to do so with the support of the citizens of Athens.
hi! you may be interested in this section of the FAQ
Did any ancient writers living in Republican Rome or in non-monarchic cities of Greece ever advocate for monarchy over democracy?
You have to remember that ancient writers almost always came from the aristocracy, which was generally opposed to both monarchy and democracy. For instance, we usually characterize ancient Rome as strongly anti-monarchial on the basis of the literary output of the senatorial aristocracy; but the fact that people advocating policies that favored the plebeians were usually accused of aspiring to kingship, and often murdered out of hand on that account, suggests that the idea of monarchy was very popular among Rome’s lower-class majority and that the Senate was constantly struggling to contain it.