Originally a Chistian feast day to honour the martyr Saint Valentine, it’s long been taken over by folk tradition to become a day of love.
What we now know as Valentine’s Day started in 15th-century France where the occasion was marked with singing and dancing.
The now-familiar custom of sending cards, flowers, chocolates started in the UK, with the first pre-printed cards being sold in the late 18th century.
It wasn't until the 20th century that Valentine’s Day became a major commercial event – notably when the Hallmark greetings card company started mass-producing cards in 1913.
Here are 21 pictures of how Valentine’s Day has been celebrated in Scotland in years past.
9. About to fold
Employees at Valentines & Sons card company, in Dundee, folding Valentine's cards in 1964. Photo: J Shearer
10. Love boat
Sailors Mark Horburgh and Scott Milligan give Lynsey Patterson a kiss as HMS Edinburgh visits her adopted city on Valentine's Day 2002. Photo: PAMELA GRIGG
11. Seven brides for seven grooms
Seven couples got married at the Gretna Green Smithy's Anvil on Valentine's Day 1989. Photo: Allan Milligan
12. Happy couple
Lyndee Cooper and Ian Adair tie the knot in Arbroath Registry office on Valentine's Day 2013. Photo: slm