Anna I of Russia (1639-1740) was either the meanest bitch in history or one of its greatest pranksters. Or both.
This story tells you just about everything you need to know about a woman who both had absolute power and was batshit insane: She once found out a nobleman had committed the offense of marrying a Catholic. In response she forced him to marry an old hag, then after the wedding ceremony dressed them up as clowns, paraded them through the streets with farm animals, stripped them naked and made them sleep in a palace made of ice. This was in Russia in the middle of winter, where taking a piss means you instantly have an icicle jammed up your urethra.
#5. Mustafa I: Just Outright Refused to Leave His Room
Being in a position of power in the Ottoman Empire during the High Middle Ages was a lot like playing King of the Hill: Everyone wanted you off the throne so they could be the target of assassination plots and political upheaval. So when Ahmed I, Mustafa's older brother, took the throne, it was a tradition to kill off all members of the family who might want a piece of the power. However, Ahmed decided to spare his brother, locking him in his room for the rest of his life instead. Dr. Phil calls that "tough love."
Fourteen years later, Ahmed was overthrown by typhoid fever. Now without a cruel ruler, the people of the Ottoman Empire decided it would be best to put Mustafa on the throne, sure there would be no side effects from the whole "life in a cage" thing.
#4. Frederick William I of Prussia: Really Liked Tall Guys
Frederick William I of Prussia (1688-1740) had a hard-on for the military. He built the most powerful army that ever graced Prussia. Also, the tallest.
See, for some reason, Fred wanted himself an army with height. He liked to display his military power by making his tallest soldiers march around (assuming they didn't need to march through the average doorway), striking fear into those of short and average height alike. You have to admit an entire army of seven-footers would be terrifying, if not really, really obvious targets.
#3. Caligula: Thought His Horse Was People
Everyone likes a good, faithful pet. That's why people hate cats. So maybe it's understandable that Emperor Caligula of Rome (12-41) would want to pamper his horse, Incintatus, as much as possible. It's kind of sweet, in a way...
... Until he started treating the horse like an actual human being. Incintatus the Horse was promoted to a consul of Rome, effectively making a horse one of the highest authorities of the time. Caligula arranged for the horse to meet the mare of his dreams (Incintatus' dreams, not Caligula's), invited him to dinner constantly and fed him gold-flecked oats.
#2. Ludwig II of Bavaria: Had Castle Fever
Ludwig II of Bavaria (1845-1866) absorbed himself completely in fantasy, probably because he realized that being a real king sucked total balls. So he decided to be an imaginary king, starting with the construction of a new castle, Neuschwanstein. He loved the castle to death, and even today it's his most famous castle, serving as the inspiration for Sleeping Beauty's Castle in Disneyland (Disney World's drunken, unkempt older brother).
#1. Saparmurat: Loved Melons, Insanity
(Note: Because Cracked cannot spell "Saparmurat "Turkmenbashi" Niyazov of Turkmenistan (1940-2006)" without copying and pasting, he will be referred to as Superman for the rest of this article.),
Just in case you missed it, check the birth and death of this guy--that is scarily recent. If you thought that crazy douches only ruled way back when, this man is very-nearly-living proof of just how fucked up things can get even today.
Superman grew up an orphan, joined the National Communist Party, made his way up the ladder and finally became president of Turkmenistan when the country gained independence. A few years later, he crowned himself President for Life and took hold of every affair in Turkmenistan.
He amassed a cult of personality, erecting statues (some made of solid gold) in his honor, establishing national holidays on his birthday and date of inauguration, and used his control of the media to praise him daily. So far, so good--seems like pretty standard eccentric dictator stuff.