A despot is a ruler who wields absolute power within his or her tribe, country or empire. Despots were common among many early human societies, an example being the early Pharaohs of Egypt. A despot's power could not be questioned, and his merest whim would be carried out as a matter of absolute necessity. A despot could also never be blamed for taking a bad decision - it was his right to do so, and his people must suffer the consequences. Often, the idea that rulers were descended from or appointed by gods was at the root of people's acceptance of this situation.
As societies have developed, despots have tended to become rarer, as people begin to believe in the fairness of rulers sharing their power with the people they rule, or even being appointed from among those people. Thus states and nations that were once ruled by despots have become constitutional monarchies or republics. In today's world, few despots exist, although some modern dictators may act like de facto despots while trying to maintain a façade of accountability for appearances' sake. A few countries such as Saudi Arabia are still absolute monarchies, but any urges their sovereigns may have to exercise their power in the manner of historical despots are largely tempered by the likelihood of popular or international opinion turning against them were they to do so.
Despots are generally associated with arbitrary, cruel and tyrannical rule, but it should be noted that this was not always the case - clearly, a despot can choose whether to exercise power justly or unjustly. In biblical times, widely admired rulers like David, Solomon and Hezekiah were all despots, as well as more infamous kings like Ahab and Nebuchadnezzar. Latterly, during the Enlightenment, rulers such as Catherine the Great of Russia were considered "enlightened despots", and many thinkers argued that a wise, despotic ruler acting in the people's interest might produce a preferable society to a democracy where everyone had a say regardless of merit.
The Italian poet Dante argued in favour of despots in his treatise De Monarchia. The thrust of his argument was that if one individual was given absolute power, they would be untainted from greed because they would already possess everything they desired; therefore, they would be freed from worldly concerns and able to act justly in the interests of their subjects.