I suspect the origin of dictatorship -- one-man rule of a social system -- is lost in prehistory. The modern form is defined as rule by one person unrestrained by constitutional law.

Any country which in which the political system is taken over by one person or by a small group of people can be a dictatorship. Often such systems have laws which supposedly restrict the dictator, but in fact he can and usually does override the law whenever it suits his purpose.

One thinks of North Korea under Kim Jong-Il as a modern dictatorship, and also of Libya under Muammar al-Gaddafi.

However, a one-party state can be a dictatorship even though it holds "elections" during which the citizens supposedly endorse the leader. For example, Mobuto governed Zaire (Congo) as a dictator even though he regularly held "elections" in which he was the only choice for head of state. Similarly, in Cuba the President is chosen every five years by the National Assembly, but since there is no limit on terms of office and since Castro controls the Assembly there is no chance of anyone but himself or someone he designates being chosen as President.

Dictatorship is very much alive in the world today.