When St. Patrick died on March 17, in 465, his death date became a national religious holiday in Ireland. On a global scale we Americans celebrate St. Patrick’s Day on March 17 as a national holiday. We celebrate the heritage and culture of the Irish in general. Celebrations generally involve public parades, class festivals, balloons, cakes and green cupcakes. We wear green attire or shamrocks. The first St. Patrick’s Day parade was held in New York City. The color for the holiday is green. Shamrocks are usually green, but you can collect purple, or white clover. What’s good luck, a four-leaf clover.