St Piran's Day started as one of the many tinners' holidays observed by the tinminers of Cornwall. Other miners' holidays of a similar nature include Picrous Day and Chewidden Thursday. There is little description of specific traditions associated with this day. However, many observers noted the large consumption of alcohol and food during 'Perrantide'. The day following the St Piran's Day was known by many as 'Mazey Day', a term which has now been adopted by the revived Golowan festival in Penzance. The phrase 'drunk as a perraner' was used in 19th century Cornwall to describe people who had consumed large quantities of alcohol.
The modern observance of St Piran's day as a national symbol of the people of Cornwall started in the late 19th and early 20th century when Celtic revivalists sought to provide the people of Cornwall with a national day similar to those observed in other nations. Since the 1950s, the celebration has become increasingly observed and since the start of the 21st century almost every Cornish community holds some sort of celebration to mark the event. Saint Piran's Flag is also seen flying throughout Cornwall on this day.
St Piran's day is also celebrated annually in Grass Valley, California to honor the Cornish miners who participated in the area's mining history beginning in the mid 19th century.
St Piran's Day Bank Holiday
In 2006, Cornish MP Dan Rogerson asked the government to make the 5th of March a public holiday in Cornwall to recognise celebrations for St Piran's Day. More recently, there has been a petition for the holiday. Some council workers in Bodmin were granted the holiday in 2006, and there have been other calls and petitions for a Cornish public bank holiday on the 5th of March. From 2009 Penzance Town Council will offer its employees a St Pirans Day Holiday following a campaign by the Celtic League.