One of my favorite traditions from my homeland (Catalonia, just across the Pyrenees from France) is Saint George's Day, which happens on the 23rd of April. Saint George is the classic medieval hero who goes around slaying dragons and rescuing princesses, and such displays of bravery earned him the title of patron saint of many places, from England to Georgia, including Ethiopia, Portugal and, of course, Catalonia.
However, contributing to the extinction of a race of legendary beasts is not what makes his day interesting. Since the 15th century, the 23rd of April has been our equivalent of Saint Valentine's Day, an excuse to celebrate love. Instead of chocolate sweets, lovers exchange red roses (something to do with the color of the blood of the slayed dragon, where a magic shrub grew as the monster lay dying).
Things get more interesting when, in the 1920s, an editor comes up with the idea of celebrating a "book day" and fill the streets with stands where people can readily buy the latest bestsellers. The first event takes place in October and it's a success, but they soon realize that a spring date would be more appropriate for such outdoor activities. And here is where Saint George gets lucky: It so happens that the 23rd of April is also the date when Miguel de Cervantes was buried and Shakespeare died, both in 1616.
