A ruler who has absolute power can be called a dictator or despot.
Chat with our AI personalities
๐๐จ๐ฏ๐๐ซ๐ง๐ฆ๐๐ง๐ญ ๐ข๐ง ๐ฐ๐ก๐ข๐๐ก ๐ญ๐ก๐ ๐ซ๐ฎ๐ฅ๐๐ซ ๐ข๐ฌ ๐๐ง ๐๐๐ฌ๐จ๐ฅ๐ฎ๐ญ๐ ๐๐ข๐๐ญ๐๐ญ๐จ๐ซ ๐ข๐ฌ ๐ค๐ง๐จ๐ฐ๐ง
I believe the correct word would be a "monarch"
An autocratic ruler has got unlimited power and usually does not allow, not even formally, that others than himself and a close follower group have a say in the government.
Tyrant
absolute monarch