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.
5. Exchanging cards
Toddlers Andrew Crossland and Catriona Morse enjoy Valentine's Day at Edinburgh's Royal Mile Nursery School in 1988. Photo: Crauford Tait
6. Valentine's pup
Puppy Balfour helps his owner Alice Shaw get ready for Valentine's Day 2013 at her shop Rogue Flowers, on Edinburgh's William Street. Photo: Jane Barlow
7. Kisses for sale
Edinburgh University students selling kisses for charity on Valentine's Day 1985. Photo: Ian Brand
8. The big day
Thomas Foster cries as Jamie Blood and Bridget Foster pose on their wedding day at the Gretna Green Famous Blacksmiths Shop on Valentine's Day 2013. Photo: Jeff J Mitchell