despotism

Arbitrary and oppressive rule of a despot or autocrat, whose decisions are not controlled by law or political institutions; another term for tyranny.

In ancient Greece, the title despot was given to the master of a household of slaves. It was later given to the absolute ruler of Eastern countries with whom the Greeks came into contact. Later still it came to be an honorary title given to princes in the Byzantine Empire, and it is still employed in something of its old sense as a mode of addressing a bishop in the Greek Church. The beginning of its present use was the use, as in the case of tyrant, of the word to describe a ruler who had no right to be the ruler although his or her government may have been beneficial.