Walpurgis Night is a traditional spring festival celebrated on April 30th or May 1st in parts of Central and Northern Europe. It originated from pre-Christian pagan spring customs but became associated with Saint Walpurga after her feast day coincided with the pagan celebrations. Early Christians incorporated pagan festivals into their traditions. In Estonia, Walpurgis Night called Volbriöö is celebrated through the night of April 30th and into May 1st with bonfires, costumes, and student celebrations in Tartu culminating in the following day known as Hangover Day.