Every year, St. Patrick's Day is celebrated across the nation and globe. People pull out all the green clothes they can find for this celebration and attend huge parades and festivals, drinking green-colored beer and partying with friends. Here are five things about St. Patrick's Day that you might not have known.

1. Saint Patrick wasn’t born in Ireland

Saint Patrick was born in Roman Britain in the late fourth century into an aristocratic Christian family. However, Patrick was not a strong believer of Christianity. As a teen, he was kidnapped and sent to work as a slave on a countryside in Ireland. Patrick was said to have heard a voice to tell him to escape, which converted him to Christianity. He then returned to Ireland to spread Christianity in the fifth century. After his death, he was named the patron saint of Ireland.

2. The Shamrock as the Holy Trinity

It is said that Saint Patrick used the shamrock to symbolize the Holy Trinity; the three leaves represent the Father, Son, and the Holy Spirit. The Shamrock has now become a symbol of Ireland.

3. Big Parades

The first parade is believed to have been held in New York City in the 1762 by Irishmen in the English military, according to the History Channel. The parade is always led by New York's 69th Infantry Regiment. Over 150,000 people participate in the parade annually. The growth of St. Patrick's Day celebrations in America continued to grow with the increase of Irish immigrants in America, with major celebrations being held in Boston, Chicago, and Philadelphia. Parades soon became an opportunity for Irish immigrants to show pride for their heritage.

4. Green, Green, Green!

Green is a color on Ireland's flag; in addition, Ireland is also known as the "Emerald Isle" because of its green landscape. Green is also the color of the shamrock, which Saint Patrick used to represent the Holy Trinity. In the 19th century, the color green became associated with a show of commitment to Ireland and the celebration of St. Patrick's Day. The tradition of pinching someone who isn't wearing green comes from the belief that wearing green makes you invisible to leprechauns, who would pinch individuals they could see who were not wearing green.

5. A Green... River?

Every year, the city of Chicago dyes the Chicago River green to celebrate St. Patrick's day. This tradition was started in 1962 by Steve Bailey, that year's parade organizer and head of a plumbers union.

Don't forget to wear green this Thursday, unless you want a leprechaun (or more likely all of your friends) to pinch you! Happy St. Patrick's Day!