here, further down the list, and has also been copied to here.
Most of the time, most of the population accepts the status quo and it would therefore be wrong to try to overthrow any current regime by force. Sometimes, it is impossible to continue running society in the old way and a majority wants change. The alternatives are a social breakdown or a new form of social organization.
Any new arrangements must quickly gain legitimacy if they are to last. Poul Anderson's Manuel Argos modeled his new Terran Empire on the ancient Roman Empire, recognizing, for example, that society would be strengthened by granting full citizenship to worthy aliens.
People building a new republic ransack history for examples of best practice. Ian Arnstein, the historian in SM Stirling's Nantucket, becomes a bore on the subject of Greek city-states!
The saying, "The King is dead; long live the King!" (here) expresses continuity but there will also be a continuity of ordered society when someone says, "The office of King is abolished; long live the Republic!" - as happened in pre-Imperial Rome.