The nursery rhymes that everyone grew up singing might have been catchy and fun to belt out with our friends, but most of them have histories dating back centuries. And these histories weren't all as lighthearted and whimsical as their corresponding tunes sound... in a twisted way, these rhymes actually tell a story of the sinister tales behind them. Not everything that's sung in a sing-songy tone is happy, and not every 'Mary' was quite 'contrary' - at least, not in the way that we associate it now.

The next time one of these nursery rhymes turns into an earworm, remember they didn't all come from places of preschool-aged children... and some of them have a much darker side to them.

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Jack And Jill, Circa 1765

The rhyme of Jack and Jill has always had a slightly inappropriate connotation to it but as it turns out, this isn't even true of the age-old nursery song. The actual spelling should be Jack and 'gill,' which is more what the rhyme was about, and less about a boy and a girl who go off to do seemingly mundane errand until misfortune strikes. Supposedly, the rhyme recounts the events that followed King Charles I's attempt at liquid tax reform.

Of course, Parliament rejected his proposed reform to lessen the tax on liquids, and rather than be satisfied with defeat, the King reduced the volume of the measurements - which were known as jacks and gills. Many believe the rhyme has to do with Louis XVI and Marie Antoinette, but the rhyme originated roughly three decades prior to the unfortunate end, so that wouldn't make much sense where timelines are concerned.

Mary, Mary, Quite Contrary, Circa 1744

The wicked beauty behind this rhyme is the seemingly innocent use of the word 'contrary' which is so tame compared to the actual story behind this rhyme. The prose speaks of Queen Mary I, who was known for taking the lives of hundreds of Protestants between the years 1553 and 1558.

She's better known by her nickname, 'Bloody Mary,' which speaks more to the gruesome trail she left in her wake as a strict believer in Catholicism. Many have mistaken the terms 'silver bells' and 'cockle shells' for things other than what they actually are, which are medieval torture devices.

London Bridge Is Falling Down, Circa 1744

London Bridge is Falling Down has several explanations as to where it originated from and none of them have a happy ending... or beginning. One of the reasons for the rhyme - and one that's highly debated amongst historians about whether it could even be close to accurate - involves human sacrifice. It was once said that due to superstitious belief, the bridge could only be built on that of sacrifice, otherwise the foundation would not hold. There is no evidence to actually support this claim, thus it became more of a horror story than an actual origin, as the rhyme entails the use of mostly children.

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The second explanation for the rhyme is one that's far more easily believed and involves a Viking attack during the year 1014. Olaf II of Norway is specifically credited for the attack that brought down the bridge, but there's also not much evidence to support this theory as certain, either. It was believed that the Vikings would sing this rhyme during many of their conquests but whether or not that makes sense is also up for debate. The last theory surrounding the rhyme is simple: It spawned from the destruction or deterioration of an old bridge. Far less exciting or dramatic than the other two, but this one actually seems to hold water - no pun intended.

Ring Around The Rosie, Circa 1881

Ring Around the Rosie has long since believed to have a sinister meaning behind its lyrics due to the Great Plague, which ravaged Europe during 1665. The connection has been drawn from the mention of 'rosie' which would have been a term for the rash which the sick would develop, and the scent of it all would be covered with 'a pocketful of posies.' It's morbid, to say the least, as the final lines of the poem would refer to, ultimately, the fact that almost 15% of London's population fell victim to the plague.

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However, according to Snopes, this origin is actually incorrect, no matter how well the lyrics seem to fit the time. The rhyme is actually believed to reference the religious ban on dancing by the Protestant church. In order to skirt the ban and find a loophole, children would engage in what was called a 'play-party,' which involved them linking hands and rotating in a circle - not quite full-on dancing, but still dancing in some form. The lack of actual music would prompt them to sing, thus the nursery rhyme that we know today.

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