"Rule by might" isn't as pervasive as you might think. It doesn't matter how tyrannical a leader might be, he still has to have the loyalty of a goodly portion of the population. Somebody actually has to act as an enforcer of the ruler's edicts, and odds are it won't be the ruler himself.
For example, Joseph Stalin was about as tyrannical as they come, but he only succeeded because there were folks loyal enough to him without coercion. And the massive population of the Soviet Union could not be kept in check through intimidation alone -- the Czars tried this and look what happened. Stalin gave the peasantry land, education, and other goodies in return for support. To this day there are folks in Russia who think ol' Uncle Joe was God's gift to creation.
That's exacty what he did.
the Czars tried this and look what happened.
It was half-liberalization that caused the Czar's problems along with bad judgements in wars.
Stalin gave the peasantry land, education, and other goodies in return for support.