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You knew them off by heart as a child and now you're a parent you can probably recite the words in your sleep.
Mums and dads have sung nursery rhymes to their kids for centuries. But have you ever wondered who the Grand Old Duke of York really was? Did you realise that Mary really did take a lamb to school?
Here, our guide reveals the fascinating origins of some of the best known ditties...
Sing a Song of Sixpence
Believed to have been referenced in Shakespeare's play Twelfth Night. Putting birds in a pie, was a real form of entertainment at grand meals during the 16th century. Another theory suggests that the rhyme is about the dissolution of the monasteries by King Henry VIII with the blackbirds as the monks, his first wife Catherine of Aragon as the 'queen' in the parlour and Anne Boleyn the 'maid' in the garden.
Ring a Ring o' Roses
Opinion is divided on whether this rhyme is really about the Black Death which swept through Europe in the 14th century killing 25million people. The explanation didn't appear until the 1950s. But many maintain that the playground favourite refers to the symptoms of the bubonic plague – the ring being the ring of sores suffered by victims before they sneeze and fall down dead!
Mary Had A Little Lamb
Dates back to 1830 and an American poem by Sarah Josepha Hale which is said to have been inspired by a real event when a girl called Mary Sawyer, living in Sterling, Massachusetts, caused commotion by taking her pet sheep to school.
The Grand Old Duke of York
One version of the song dates back to 1642, but in this the culprit is the King of France. There are several candidates for the later version featuring the Duke of York. The most likely is Prince Frederick, Duke of York and Albany. He was the second son of George III who led a disastrous campaign in Flanders, following the French Revolution.
Georgie Porgie
Mad King George III's first son was also the subject of a rhyme. As Prince Regent and then George IV he was famous for his womanising and often lampooned in satirical cartoons of the time. He was also famous for his enormous appetite and, when he died, he had a waist measuring 50 inches.
Pop Goes the Weasel
Goes back to the 1850s with some suggesting that 'pop goes the weasel' was a reference to pawning goods. The Eagle in the rhyme was a real pub, which still exists, just off the City Road in London. It was then a music hall.
Little Miss Muffet
First seen in print in 1805 but thought to date back to Dr Thomas Muffet, known to have studied spiders in the 16th century. It's suggested that he wrote it about his stepdaughter Patience.
Baa, Baa, Black Sheep
The rhyme dates back to at least the 1731 and is most likely to refer to the wool tax imposed in the 13th century. In this theory the master is the king, the dame is the monasteries of the time who each had a claim on the proceeds.
Ride A Cock Horse...the Banbury Cross
The rhyme has been associated with both Lady Godiva, who famously rode a horse nude, and Queen Elizabeth I who once visited Banbury. No one knows for sure but it is recorded as far back as the 18th century and the fashion for wearing bells on the ends of shoes was popular at the end of the 15th century.
London Bridge is Falling Down
Goes back at least as far as the 17th century and there are similar old rhymes from Denmark, Germany and France. One theory has it that the rhyme refers to the sacking of the bridge by Olaf II of Norway in 1014. Others suggest that it simply refers to the old medieval London Bridge which, by the 18th century, was in a state of disrepair.
Jack and Jill
Jack and Jill as a 'pair' go back to the 16th century with Shakespeare referring to them in his play A Midsummer's Night Dream. There are several theories but the village of Kilmersdon in Somerset lays claim to be the source and there is a stone tablet recording it.
In 1697 an unmarried couple were said to have done their courting on the hill. Jill fell pregnant but before the baby was born Jack was killed by a rock that fell off the hill. Jill is then said to have died in childbirth!
Rock-a-bye Baby
The rhyme first appeared in the 18th century and one theory suggests that it is about native American women who used to rock their children in wooden cradles suspended in trees.
Humpty Dumpty
The words first appeared in the late 18th century and the tune in 1870. There are several theories as to what Humpty Dumpty was. One suggests that it was actually the nickname of a cannon used on the walls of Colchester by the Royalists during the Civil War. It was used to repel the Parliamentarian forces attacking the town, but was eventually blown up and came crashing down – never to be put back together again.
Little Jack Horner
It's thought that Jack Horner was actually Thomas Horner a steward to Richard Whiting, the last abbot of Glastonbury put to death under King Henry VIII. The story goes that in a bid to stop his abbey being destroyed the abbot had sent Horner to the King with a huge Christmas pie, secretly containing the deeds to 12 manor houses as a sweetener. But Horner arrived with only 11, taking one for himself. Whatever the truth, the ploy didn't work. The abbey was torn down anyway.
Doctor Foster
In the verse the word puddle is rhymed with middle and some researchers believe that it was originally piddle, which once meant a stream. This gives weight to the theory that it relates to a story about Edward I, King of England in the 13th century, who, whilst visiting Gloucester during a storm, rode his horse through a stream which was deeper than he thought and had to be pulled out.
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