Saint Patrick, the man behind St. Patrick's Day holiday, wasn't even Irish

• St. Patrick's Day is celebrated on March 17 because that's the day historians believed he died.
• The holiday wasn't always the way we see it today. It was once a solemn time in Ireland where bars remained closed.
• Though credited with spreading Christianity in Ireland, St. Patrick didn't really drive out the snakes from the island.

Who was Saint Patrick and why do we celebrate him? Saint Patrick is the protecting and guiding saint of Ireland. Ironically, he was not Irish. 

Saint Patrick went from being sold into slavery to being credited to bringing Christianity to Ireland, according to Elizabeth Stack, executive director for the Irish American Heritage Museum in Albany, New York.

"He had a dream that the Irish were crying for him that they needed him," Stack said. "He returns to Ireland and brings Christianity with him. He is who made the Celts and the pagans into Christians."

St. Patrick's Day is celebrated on March 17, the day he is assumed to have died. The holiday originally was tied to religious ideals but now is also a symbol of Irish pride. 

According to Stack, until around 40 years ago, it was a very traditional, religious and solemn time in Ireland. Bars even remained closed. 

But things have changed. Fun symbols such as wearing green, leprechauns and shamrocks have been popularized during this holiday. Yet, what are their actual meanings?

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Who was St. Patrick?

Saint Patrick was born in Britain in 386.

At 16, he was captured by pirates and brought to Ireland where he was sold as a slave, according to Stack.

"He spent his days and his nights in the fields tending the sheep and praying, a steady routine of prayer and labor which reshaped the rest of his life," Matthew Paul Grote, a Catholic priest with the Order of Preachers, said in a statement to USA TODAY. "It was after six years of this that he heard the voice of God in a dream, directing him to a boat which would take him home."

Patrick escaped to France in 408 A.D, and eventually found his way to his family and to Ireland, according to Stack. 

He was ordained as a bishop in 432 A.D., and sent by Pope Celestine I to Ireland to spread Christianity and support the Christians already living there. To fight the resistance toward Christianity, he incorporated pagan rituals into church practices. 

"Patrick became inflamed with the desire to help alleviate the suffering of the Irish people who were burdened under the yoke of slavery, brutal tribal warfare and pagan idolatry. It was in the midst of this vocational experience that he understood his call to become a Catholic priest," Grote said in an emailed statement.

According to Grote, Patrick was repeatedly attacked and captured by Irish clans. However, Patrick used non-violent approaches and would willingly surrender. He would then use this opportunity to teach the Catholic faith. 

Saint Patrick died in 461 A.D. presumably on March 17, the date he is now celebrated.

"Patrick is an icon of the Gospel message of love and forgiveness, and all the hard work and social effort that hard work takes in real life," Grote said.

Why is Saint Patrick important?

St. Patrick is the one who brought Christianity to Ireland. He wrote two books, "Confessio," a spiritual autobiography, and a "Letter to Coroticus," where he urged the British to quit the mistreatment of Irish Christians.

There are legends surrounding St. Patrick, such as crediting him with eradicating snakes from Ireland and that he saved the high king of Ireland, Stack said.

"They said he drove the snakes out of Ireland, but actually there weren't wouldn't have been snakes in Ireland anyway because the climate is not good for snakes," said Stack. "The snakes were a symbol for pagans, so he got rid of all the pagans."

What is St. Patrick's Day?

St. Patrick's Day is celebrated globally on March 17. The day also falls during the Christian holiday of Lent, a 40-day period filled with prayer and fasting.

Irish Christians attend church in the morning and then celebrate in the afternoon. The Catholic holiday has been celebrated since the 8th century in Ireland.

Surprisingly the earliest record of a St. Patrick’s Day parade took place in St. Augustine, Florida, not Ireland, in 1601. At the time, it was a Spanish Colony. The parade and a St. Patrick’s Day celebration a year earlier were organized by the Irish vicar Ricardo Artur, according to Stack.

How did it come to the United States?

The Irish immigrant population grew in America following the potato famine. The first parade was in New York in 1762, but became a yearly thing in 1851 when Irish Aid societies started to throw annual parades. Being especially big in New York, that parade is now considered the world‘s oldest civilian parade and the largest in the U.S., with over 150,000 participants, according to History.com.

Initially, the Irish faced rejection from the U.S. being categorized as heavy drinkers and uneducated in newspaper cartoons. However, as they grew in numbers, they started to have political power. They used St. Patrick's Day as a holiday to celebrate their heritage. 

"The parade started with Irish American soldiers trying to demonstrate their loyalty to America," said Stack. "The parade was a way to show they could be good American citizens."

That tradition then got sported back to Ireland. The parades are now tools to encourage tourism, export Irish culture, heritage and music, Stack said.

"It is supposed to be a day to feel proud to be Irish, but growing up in Ireland, it was more about a day off school," Marigold White told USA TODAY.

An Irish national who has lived in the U.S. but currently lives in Australia, White said, "As an adult and especially living overseas from Ireland, it has had cultural significance, though I do get embarrassed sometimes by the excuse for Irish people to use the day just to get drunk. There is so much more about Ireland to celebrate."

What's the deal with the shamrock? 

One of the legends surrounding St. Patrick is the way he used the shamrock to teach others about Christianity. Allegedly, he made an analogy to the Holy Trinity with the shamrock.

He explained how the shamrock has three leaves but it is still one flower. This parallels the Holy Trinity, where there is the God, the Son, and the Holy Spirit, yet still one entity. The shamrock is now the official flower of Ireland and worn to commemorate St. Patrick's Day, according to Stack.

OK, but what about the leprechaun?

The leprechaun came from the idea that the Celtics believed in fairies and other magical beings that use their powers to scare away evil. It is presumed that the association came from the popular 1959 Disney movie "Darby O’Gill & the Little People," which features Irish leprechauns, says Stack.

Stack also attributes Lucky Charms as a way the leprechaun got popularized in the USA.