Dictator is a ruler of a country or a group of countries. The style of ruling is “totalitarianism” – concentration of power in hands of one person or family; no political opposition; limited freedoms and rights of people etc.
During the history of the world there were a lot of world dictators practically in all countries.
Napoleon Bonaparte started his career as a military officer and soon became the Emperor of France. He started conquering Europe aiming to extend the limits of French Empire. General Kutuzov routed Napoleons army and this was the start of the Empire’s decay. Napoleon was dethroned and banished to a lonely deserted isle where he ended his days.
Adolph Hitler came to power as a German Chancellor elected by the ruling national-socialist party. He wanted to install the domination of the Third Reich, but was routed by the coalition of Soviet Union, Great Britain and USA.