I am not going to get into the Roman-British born non-Irish St. Patrick or how he drove the snakes (Druids) Out of Ireland. I think there is enough information about that around.
What I want to discuss is how Christianity hijacked another holiday and replaced gods with their own.
Just what do the Shamrock, Leprechaun, or a pot of gold at the end of a rainbow have to do with Catholicism? Well Nothing.
The shamrock was a symbol for the goddess Brigit and the scared number three. Often (and still) fairy tales were told in terms of threes, something happens, something else happens, and then on the third time a change. (three little pigs, Three billy goats gruff, etc) 3 dominated story telling, songs, and verses. The Shamrock 3 leaves were symbolic of this three set world view (past present future, earth, sky, underworld, love, wit, valor. It was not the symbol of the holy trinity of father son and holy ghost. But that is what it became based on legends on St. Patrick's teaching.
Leprechaun are not magical tiny grumpy shoe makers with hidden gold with the ability to disappear. They used to be a kind of fairy (and fairies are mean). And they had nothing to do with St. Patrick's Day and were not even that associated with the Irish until 1959 when Walt Disney put out a film called Darby O'Gill & the Little People.
Which made Leprechaun fashionable and created a pop-icon for Ireland in America. This was further pushed by Lucky for General Mills a shamrock sporting all green wearing wearing Leprechaun.
St. Patricks Day is far different in the US than in Ireland. For one the people in Ireland are actually Irish, and secondly nobody in Ireland wears green on St. Patties Day. That just a US thing. The reason is that Irish Americans did this as a way of showing solidarity and gaining political power as their numbers increases in North East Cities after two potato famines in Ireland.
The pot of gold at the end of a rainbow comes from an old story I am not making claims because I don't want to argue about it (as I recently was) but lets just say a disputed old story. It was a fairy tale and in in the fairy tricked a farmer telling him that their gold was at the end of a rainbow. Of course there is no end to a rainbow and it would be impossible to chase one down and find any gold. This drove the seeker mad trying to chase after a rainbow when one appeared and never find the gold. It's typical for fairies to play tricks on human particularly based somehow on their greed or ignorance of nature.
St. Patrick himself made conversions in the Royal Family and slowly through force, fear, law, and bribery, Christian missionaries converted the Irish to monotheism. Later the sect of Christian would divide again to assure that there would never be peace and the Irish would still have something religious to fight over.
The conflict between Northern Ireland (West Britain) and Ireland proper however had nothing to do with religion. It was political and began as a strike against the British who were using Irish soldiers in WWI. And yet WWI had nothing to do with Ireland it was England's war. I say England and not wales or Scotland because it was the Bank of England financing the mess. You guys know all about that mess.
Anyway it soon morphed into a religious conflict as the British fought the gurilla war back buy randomly killing Cathoilcs thus kicking off revenge murders by equally crazy Catholics on Protestants. Divide an conquer and use religion to do it. The sad history of Ireland getting duped by the British into fighting one another. (Same thing done earlier to the British by Rome)
Anyway now its a secular holiday its even in Japan and it serves as an excuse to wear green, drink Irish beer, and spirits (Bailey's etc) and have green foods drinks and so on.
Happy St. Patricks Day.
Ryan (Irish name)
I wonder if General mills, Disney of St. Patrick's Day have talked to Coca-Cola of Santa's uniform on Christmas. Funny how much influence corporations can have on the deepest parts of culture and few people know about it.
Hidden history of Christmas
Hidden History of Halloween
Hidden History of Thanksgiving (and Columbus Day)