Half a millennia later people started celebrating his life on the day of his death. As a religious holiday, the day is traditionally observed by attending church services in the morning and celebrating in the afternoon. Since the holiday falls in the middle of Lent, restrictions against eating meat and drinking alcohol are lifted for those 24 hours. On March 17, 1762 the first St. Patrick's Day parade was held... in New York City, by Irish soldiers serving in the English army trying to reconnect to their roots. In 1903 the day became an official public holiday in Ireland. Soon after, due to the day-long break from Lent, drinking got out of hand and a law was passed mandating all pubs to be closed on March 17th... which lasted until the 1970's.
Today they combine it all: the church-going, parade-watching, pub-crawling all.