Are you in dire need of some icebreakers to spice up your social life? Are you turning green with anxiety because the long awaited holiday has finally come, but you can’t tell your friends about the history of St. Patrick? Today, you’re in luck.

To start, St. Patrick’s Day was originally a religious holiday to celebrate Irish culture, specifically celebrating St. Patrick, the Patron Saint of Ireland. The day falls on the alleged anniversary of his death, March 17th, because he brought Christianity to Ireland, which is a highly celebrated achievement. While now you may know St. Patrick’s Day as the one day a year where you’re allowed to pinch your friends and family, associated with merch of red-headed leprechauns and pots of gold, it wasn’t always that straightforward. 

This day was originally celebrated exclusively in Ireland until in 1762, when homesick Irish soldiers stationed in New York City marched to Irish music to commemorate their culture, which allowed enthusiasm for the holiday to grow in America. Even so, in an era that took religious affiliation very seriously, the majority of Americans were Protestant and didn’t celebrate this holiday out of a disconnect from Irish culture; however, this changed during the infamous Potato Famine in 1845 as many Irish Catholic people immigrated to America to escape starvation. 

The American Protestant majority resisted this new cultural group because of their beliefs, seeing the Irish Catholics as violent or drunk when they took to the streets to celebrate; however, the Irish Catholics offset this hostility when they realized their significant numbers, and were able to swing political votes. Thus, they nicknamed themselves the “Green Machine,” and the use of green as a symbol for the Irish was born. American Irish people further won over America when in 1948, President Harry Truman attended New York’s St. Patrick’s Day Parade, showing his support to the cause.   

Now, let’s look at another iconic tradition for St. Patrick’s Day in the US.  In Chicago, when pollution-control workers would use dye to see illegal sewage discharges, they realized that they could dye the Chicago River green to support Irish culture, particularly on St. Patrick’s Day. 1962 was the first year that they did this; workers poured 100 pounds of green vegetable dye into the river, turning the water a brilliant green for a whole week. Since then, the measurements have been decreased to around only 40 pounds, but Chicago has kept this unique tradition alive to continue their support for St. Patrick’s Day. 

Now, you may be wondering: If  St. Patrick’s Day is a religious holiday celebrating Irish culture, how did it evolve into pinching someone if they weren’t wearing green? Surely it’s not because if you aren’t in green you don’t support Irish culture? Well, it is actually the opposite! Leprechauns–the cranky, tiny, men we are familiar with–were first seen in Irish folklore stories/tales, and are now celebrated on March 17th via a variety of St. Patty’s merch. In folklore, they would pinch anyone they can see. However, according to these tales, they cannot see anyone in the color green, as they appear invisible. This is why you are allowed to pinch someone not in green on St. Patrick’s Day, to signify that the Leprechauns can see you–and want to pinch you. (But be warned, there are rules to pinching on the 17th: You must wear green clothing, and it must be visible to everyone. If you are following these rules and someone pinches you, you’re allowed to pinch them back!)

Now that you know why we celebrate St. Patrick’s Day (and some rules about pinching), celebrate Irish culture, be ready with your green, and watch out for pesky Leprechauns!