It's renowned for being the 'most romantic day of the year'.
And many of us use it as an opportunity to show affection for our loved ones with cards, flowers or chocolates.
But why exactly do we celebrate Valentine's Day and why does it fall on February 14?
Well The Mirror trawled through the history books to find out the real reasons so you don't have to - and the background casts a very different light on the holiday.
How did Valentine's Day begin?
A sold out sign is seen in front of heart shaped chocolate lollipops on display at a department store in Tokyo, Japan. In Japan Valentine's day is celebrated differently from Western countries. On Valentines day Japanese women are expected to give chocolates to the men, some are given as courtesy or friendship gifts to male friends, colleagues or classmates, others are given to a women's "one true love". (Photo: Chris McGrath/Getty Images)
Valentine's Day is an old tradition thought to have originated from a Roman Festival known as Lupercalia, according to History.com.
It was held on February 15 as a fertility festival dedicated to Faunus, the Roman god of agriculture.
During the celebrations boys would draw names of girls from a box and the pair would be partners during the festival.
These matches often led to marriage.
The festival survived the initial rise of Christianity but was outlawed at the end of the 5th century when Pope Gelasius declared February 14 St Valentine's Day.
Chaucer may have actually made it all up
Chaucer, as in The Canterbury Tales writer, may have actually been behind Valentine's Day. The medieval English poet took quite a few liberties with history. He'd drop his poetic characters into real-life historical events leaving readers wondering if that's what really happened.
There is no actual record of Valentine's Day before Chaucer's poem in 1375. It's in Parliament of Foules that he links the tradition of courtly love to the St Valentine's feast day - the tradition didn't exist until after his poem.
The poem refers to February 14 as the day of birds coming together to find a mate. “For this was sent on Seynt Valentyne’s day / Whan every foul cometh ther to choose his mate,” he wrote and maybe invented Valentine's Day as we now know it.
Who was St Valentine?
St. Valentine
The St Valentine that inspired the holiday may have been more than one man.
The saint officially recognised by the Roman Catholic Church was a real person who died around AD 270.
An account from 1400s describes Valentine as a priest who was beheaded by Emperor Claudius II for helping Christian couples wed.
The emperor had banned marriage as he thought single men made better soldiers. Valentine felt this was unfair so he celebrated marriages in secret. When the emperor found out he was thrown in jail and sentenced to death.
He may also have been Bishop of Terni, also martyred by Claudius II on the outskirts of Rome. There are similarities between the priest's and bishop's stories, which leads people to believe they are the same man.
There's so much confusion around St Valentine that the Church stopped veneration of him in 1969 - though he is still listed as an official saint.
“Valentinus” is from the Latin word for worthy, strong or powerful, and was a popular name between the second and eighth centuries AD meaning there are several martyrs with the same name. There are actually a dozen Valentines listed and there's even a Pope Valentine. The actual day we celebrate is known as St Valentine of Rome to set him apart.
What does he really have to do with love?
Valentine did help marry couples in secret, which is arguably very romantic. He is the patron saint of beekeepers and epilepsy among other things..like the plague, fainting and travelling. That doesn't stop people calling on his help for those romantically involved. He's now also patron of engaged couples and happy marriages.
Why is his skull kept in Rome?
l is housed and adorned in flowers in Rome. It's actually on display in the Basilica of Santa Maria in Cosmedin.
It was found when people were excavating a catacomb near Rome in the early 1800s. The skeletal remains and other relics now associated with St Valentine were dug up. It's the norm for these to be split and distributed to reliquaries - places that keep relics - around the world. If you wanted to see other parts of the saint, he's on display in the Czech Republic, Ireland, Scotland, England and France.
Why do we give Valentine's cards?
Heart-shaped Valentine card with Cupid. It was printed by the prodigious Raphael Tuck & Sons and dates from the 1880s. Price £20. (Photo: Altus Arts Proudlove antiques col)
Another idea is that when he was sent to prison, he sent a letter to a young girl he had fallen in love with and signed it "From your Valentine".
It's thought this was the first ever Valentine's Day greeting .
Why is always celebrated on February 14?
Some believe that Valentine's Day's is celebrated mid-February to mark the anniversary of St Valentine's death.
It's thought to have happened in the middle of the month around 270 AD.
Others maintain that the Christian church decided to place St Valentine's feast day at this time of the year in an effort to 'Christianise' the pagan festival of Lupercalia.
Why are roses associated with Valentine's Day?
Roses have been the symbol of love since the early 1700s when Charles II of Sweden brought the Persian poetical art known as the "language of flowers" to Europe.
Throughout the 18th century, ladies loved their floral dictionaries, which listed the symbolic meanings of different flowers.
The red rose was believed to be the flower favoured by Venus, the Roman Goddess of Love, and has therefore come to represent that.
Why cupid?
Cupid is the god of desire, erotic love, affection and attraction. He is the son of Venus, goddess of love, and war god Mars. Cupid in Latin is 'amor', which means love.
When did Valentine's Day become commercial?
It wasn't until the 18th century that Valentine's Day took off in England. Lovers began to send trinkets, cards and flowers to their loved ones. A huge amount of printed cards would get sold, then in 1913 Hallmark Cards in Kansas City began mass producing specific Valentine's Day cards. Now about a billion cards are sold every year and it's the second biggest card sending time of the whole year.
Why do we sign cards anonymously?
Apart from the embarrassment, there was an actual tradition started by the Victorians. They thought it was bad luck to sign the cards with their actual names. It was also the Victorians that sent roses as they were Venus' favourite flower.
Valentine's Day inspiration
Valentine's Day has developed a reputation for consumers splashing out on fancy candy, lavish gifts and expensive holidays - but it's not always the cash that counts.
And many of us use it as an opportunity to show affection for our loved ones with cards, flowers or chocolates.
But why exactly do we celebrate Valentine's Day and why does it fall on February 14?
Well The Mirror trawled through the history books to find out the real reasons so you don't have to - and the background casts a very different light on the holiday.
How did Valentine's Day begin?
A sold out sign is seen in front of heart shaped chocolate lollipops on display at a department store in Tokyo, Japan. In Japan Valentine's day is celebrated differently from Western countries. On Valentines day Japanese women are expected to give chocolates to the men, some are given as courtesy or friendship gifts to male friends, colleagues or classmates, others are given to a women's "one true love". (Photo: Chris McGrath/Getty Images)
Valentine's Day is an old tradition thought to have originated from a Roman Festival known as Lupercalia, according to History.com.
It was held on February 15 as a fertility festival dedicated to Faunus, the Roman god of agriculture.
During the celebrations boys would draw names of girls from a box and the pair would be partners during the festival.
These matches often led to marriage.
The festival survived the initial rise of Christianity but was outlawed at the end of the 5th century when Pope Gelasius declared February 14 St Valentine's Day.
Chaucer may have actually made it all up
Chaucer, as in The Canterbury Tales writer, may have actually been behind Valentine's Day. The medieval English poet took quite a few liberties with history. He'd drop his poetic characters into real-life historical events leaving readers wondering if that's what really happened.
There is no actual record of Valentine's Day before Chaucer's poem in 1375. It's in Parliament of Foules that he links the tradition of courtly love to the St Valentine's feast day - the tradition didn't exist until after his poem.
The poem refers to February 14 as the day of birds coming together to find a mate. “For this was sent on Seynt Valentyne’s day / Whan every foul cometh ther to choose his mate,” he wrote and maybe invented Valentine's Day as we now know it.
Who was St Valentine?
St. Valentine
The St Valentine that inspired the holiday may have been more than one man.
The saint officially recognised by the Roman Catholic Church was a real person who died around AD 270.
An account from 1400s describes Valentine as a priest who was beheaded by Emperor Claudius II for helping Christian couples wed.
The emperor had banned marriage as he thought single men made better soldiers. Valentine felt this was unfair so he celebrated marriages in secret. When the emperor found out he was thrown in jail and sentenced to death.
He may also have been Bishop of Terni, also martyred by Claudius II on the outskirts of Rome. There are similarities between the priest's and bishop's stories, which leads people to believe they are the same man.
There's so much confusion around St Valentine that the Church stopped veneration of him in 1969 - though he is still listed as an official saint.
“Valentinus” is from the Latin word for worthy, strong or powerful, and was a popular name between the second and eighth centuries AD meaning there are several martyrs with the same name. There are actually a dozen Valentines listed and there's even a Pope Valentine. The actual day we celebrate is known as St Valentine of Rome to set him apart.
What does he really have to do with love?
Valentine did help marry couples in secret, which is arguably very romantic. He is the patron saint of beekeepers and epilepsy among other things..like the plague, fainting and travelling. That doesn't stop people calling on his help for those romantically involved. He's now also patron of engaged couples and happy marriages.
Why is his skull kept in Rome?
l is housed and adorned in flowers in Rome. It's actually on display in the Basilica of Santa Maria in Cosmedin.
It was found when people were excavating a catacomb near Rome in the early 1800s. The skeletal remains and other relics now associated with St Valentine were dug up. It's the norm for these to be split and distributed to reliquaries - places that keep relics - around the world. If you wanted to see other parts of the saint, he's on display in the Czech Republic, Ireland, Scotland, England and France.
Why do we give Valentine's cards?
Heart-shaped Valentine card with Cupid. It was printed by the prodigious Raphael Tuck & Sons and dates from the 1880s. Price £20. (Photo: Altus Arts Proudlove antiques col)
Another idea is that when he was sent to prison, he sent a letter to a young girl he had fallen in love with and signed it "From your Valentine".
It's thought this was the first ever Valentine's Day greeting .
Why is always celebrated on February 14?
Some believe that Valentine's Day's is celebrated mid-February to mark the anniversary of St Valentine's death.
It's thought to have happened in the middle of the month around 270 AD.
Others maintain that the Christian church decided to place St Valentine's feast day at this time of the year in an effort to 'Christianise' the pagan festival of Lupercalia.
Why are roses associated with Valentine's Day?
Roses have been the symbol of love since the early 1700s when Charles II of Sweden brought the Persian poetical art known as the "language of flowers" to Europe.
Throughout the 18th century, ladies loved their floral dictionaries, which listed the symbolic meanings of different flowers.
The red rose was believed to be the flower favoured by Venus, the Roman Goddess of Love, and has therefore come to represent that.
Why cupid?
Cupid is the god of desire, erotic love, affection and attraction. He is the son of Venus, goddess of love, and war god Mars. Cupid in Latin is 'amor', which means love.
When did Valentine's Day become commercial?
It wasn't until the 18th century that Valentine's Day took off in England. Lovers began to send trinkets, cards and flowers to their loved ones. A huge amount of printed cards would get sold, then in 1913 Hallmark Cards in Kansas City began mass producing specific Valentine's Day cards. Now about a billion cards are sold every year and it's the second biggest card sending time of the whole year.
Why do we sign cards anonymously?
Apart from the embarrassment, there was an actual tradition started by the Victorians. They thought it was bad luck to sign the cards with their actual names. It was also the Victorians that sent roses as they were Venus' favourite flower.
Valentine's Day inspiration
Valentine's Day has developed a reputation for consumers splashing out on fancy candy, lavish gifts and expensive holidays - but it's not always the cash that counts.
