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Caligula -

The Roman emperor Caligula is notorious for his strange sexual appetites, particularly after the 1979 film 'Caligula' starring Malcolm McDowell. However, his greatest obsession was his horse, Incitatus.

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Caligula -

Caligula reportedly had a marble stall and a house built for the horse, and would invite him to dinners where he was fed oats with flakes of gold. There were even rumors that he made his horse a consul!

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Ludwig II of Bavaria -

King Ludwig II of Bavaria was known as "Mad King Ludwig." He became king when he was a teenager and was devoted to the arts, particularly music and architecture.

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Ludwig II of Bavaria - His obsession was one fit for a king. He was fixated on building luxurious castles with fantastical designs. He's responsible for ordering the building of the famous Neuschwanstein castle in Bavaria, which many believe was the inspiration for Disney's Cinderella castle.

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Friedrich Wilhelm I -

Friedrich Wilhelm I spent much of his reign expanding the Prussian army and creating a personal regiment of his own unique soldiers. Based on historical accounts, it seems like he was trying to build a team of giants.

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Friedrich Wilhelm I -

The requirement to join this special regiment was to be at least six feet (183 cm) tall. He would search for viable candidates and pay men for their tallest son or farmhand. He even tried to stretch men on the rack to make them taller, but only injured or killed them.

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Vlad the Impaler - In the case of Vlad III, his nickname kind of gives it away. Vlad the Impaler was a notoriously violent leader, showing his enemies no mercy.

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Vlad the Impaler -

He was known for impaling his enemies on spikes and leaving their bodies on display. Hence the name! 

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Emperor Qin Shi Huang - Qin Shi Huang is considered to be the first emperor of China. Despite his obvious success, he was consumed by a quest to achieve ever-lasting life.

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Emperor Qin Shi Huang -

He spent a great deal of his time and resources looking for the answer. He would drink potions created by his alchemists, which ironically lead to his untimely death when he drank a potion made of poisonous mercury.

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Princess Alexandra of Bavaria -

Princess Alexandra of Bavaria had a highly obsessive personality. She was fixated on cleanliness and would only wear white. She also suffered from a bizarre delusion that was common among nobility from the 15th to 17th centuries, called the "glass delusion."

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Princess Alexandra of Bavaria -

In Alexandra's case, she one day started to believe that she had swallowed a full-size piano made of glass. She began walking very carefully and passing through doors sideways, believing she had to be very careful to not shatter the glass inside her.

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Napoleon Bonaparte -

Napoleon Bonaparte's complexities are well recorded. Well, one of his stranger obsessions was liquorice.

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Napoleon Bonaparte -

He reportedly carried liquorice with him everywhere and ate it daily. He consumed it for both enjoyment and as a treatment for various ailments. He ate so much that his teeth were stained black.

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Nero -

The Roman emperor Nero was known for his tyrannical reign, and it's rumored that he started the Great Fire of Rome. It's also rumored that he had a fondness for killing, and murdered his mother, one of his wives, and his step-brother.

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Nero -

However, his greatest obsession was killing Christians. He blamed them for the Great Fire and began persecuting them mercilessly. He came up with creatively sadistic ways to dispose of them, such as feeding them to wild animals.

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Peter III of Russia -

Peter III was one of the less impressive and shorter ruling czars of Russia. He is the subject of the recent Hulu series 'The Great,' where he is shown to be frivolous and childish.

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Peter III of Russia -

According to the memoirs of his wife, Catherine the Great, he really just wanted to play with his toys. He had a large collection of dolls and toy soldiers and would sometimes bring them into the bed and force her to play too.

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Louis XIV -

Louis XIV ruled France for 72 years. Like many nobleman during this period, he believed enemas contributed to good health and longevity, and used them often.

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Louis XIV -

Unlike other noblemen, he is said to have been a bit obsessed. Some sources say he did thousands of enemas in his lifetime!

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Ivan the Terrible -

Ivan IV was one of the cruelest czars of Russia. He was known for his extreme paranoia and reign of terror.

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Ivan the Terrible -

It's rumored that his obsession with inflicting pain began at young age, with animals. He would capture birds and torture them, or find stray cats and dogs and throw them from high windows.

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Fyodor I of Russia -

Fyodor I was the son of Ivan the Terrible, but he had very different hobbies to his father. He was devoutly religious and spent much of his time in churches.

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Fyodor I of Russia -

His favorite activity was ringing the church bells to call in the parishioners. He became known as "Fyodor the Bellringer."

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Ibrahim I -

Ibrahim I was an Ottoman sultan who earned the name "Ibrahim the Mad." He is remembered for his extensive harem of concubines and strange sexual appetites.

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Ibrahim I -

It seems he became bored with the hundreds of women in his harem, and became obsessed with the bodies of female cows. He ordered a search for a woman with similar proportions, and apparently found them in a large Armenian woman whom he called "Sugar Cube."

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Joanna of Castile -

Queen Joanna I of Castile would be remembered in history as "Juana the Mad." She was married to King Philip, who is said to have been frequently unfaithful to her. This drove her into fits of rage and despair.

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Joanna of Castile -

When he died at the age of 28, Juana refused to be parted with his corpse. She stayed with it until he was interred, but then commanded the coffin be opened again. She later had it brought with her everywhere she traveled, protected by armed guards so other women couldn't reach it.

Sources: (History) (Ranker)

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