With the upcoming election and the usual barrage of Chicago style mud slinging, accusations and scandal I had to appreciate the fact that as bad as it can get at least it's a bit easier to get rid of an unstable leader. I can't imagine the helpless uneasiness the subjects of some of the less stable rulers must have been watching their leader deteriorate.
Rome had some outstanding examples. Caligula ruled for only 4 years, but he managed to have quite an impact. He actually started out doing fairly well. He took over when Tiberius, his grand-uncle died. Tiberius was in the middle of very unpopular and painful search for those he considered treasonous. Lots of people had been tortured and killed, imprisoned and stripped of their property. Caligula, in a gesture of good will, reinstated property, released people from prison and nixed the torture spree. For a bit.
Not long after taking power, he grew very ill and when he recovered he was a very different man. His behavior became more erratic and extreme. He took on a lavish lifestyle, going rapidly through the government's funds and heaping taxes on his subjects to pay for his indulgances. He is suspected of having incestuous relationships with all three of his sisters, he had an affair with his chamberlain, Marcos, wife and then accused Marcos of being a pimp and ordered him to commit suicide. He took what women he wanted with no regard for marital status, rank or the woman's opinion of the matter.
The treason trials began again, it became mandatory to bequeath the emperor everything you owned and wealthy subjects were murdered quite frequently, their wealth then going to Caligula.
He attempted to make his favorite horse a consul and at one point embarked on a military campaign to invade Britain which resulted in the troops being ordered to collect sea shells as trophies of the campaign.
He was assassinated by his own guards who were part of a conspiracy involving several high ranking senators. His wife and small daughter were murdered as well.
According to a historian named Svetanius, Caligula suffered from epilepsy, called parliamentary disease and which was considered to be a very bad omen for a ruler to have. His was a chaotic if short reign.