America’s first St. Patrick’s Day parade happened before the Revolution in Boston, as a protest against unfair treatment of Irish soldiers in the British Army as well as a celebration of St. Patrick.
In the 1840’s, Boston was divided between the huge, mostly extremely poor Irish population who had lost their whole world and watched their loved ones die, and a very anti-Irish older New England population who wanted the Irish out. It was almost impossible to survive without ethnic associations for anyone in that time and it was flat out impossible for the Irish. So, lacking a hall to meet in as other ethnic groups had, the Irish walked home from Mass together and talked business then. They wound through the streets, seeing people safely home to avoid ethnic violence. Some joind in late, having had to work, and some joined more than one parade, to talk to various people. However, some people joined the parades to attack the Irish. So a way of distinguishing hese newcomers was needed. They started handing out more and more visible ribbons, hatbands, kerchiefs, badges, etc. as they walked. Anyone who wouldn’t put one on was known to be an enemy and thrown out. That’s why wearing something green, particularly a hat, scarf, ribbon, pin or shamrock (or whole outfit) is common today even for people who have no Irish blood. It’s the custom to pinch anyone who refuses to wear any green at all. But that’s more a children’s custom. It came from a real, scary and not-that-long-ago reality of violence against the Irish and their need to defend themselves.
Buying someone a drink during the parade was a way of talking more privately or doing some business. It wasn’t meant as an excuse to get drunk. It was just much cheaper than buying food. sometimes people were far from home, and some were homeless or lived in one room with twenty-plus people they didn’t know much about. So they met at bars to talk.
Cheap, filling food was a way of celebrating any holiday in that culture. They went hungry between feasts to save enough to buy a little corned beef (the cheapest meat) and cabbage (the cheapest vegetable) to share with friends and family.
The Civil War and both World Wars saw the Irish set themselves above others as soldiers so well that gradually the stigma of being Irish faded and the St. Patrick’s Day parades spread as a way of demanding respect for fighting for America.
The decorations in the stores nowadays showing drunken, foulmouthed leprechauns are a holdover from anti-Irish stereotype propaganda from the 19th Century. I won’t wear or buy anything like that. My decorations are simple green streamers and such. I wish I could find some with positive images on them but I can hardly find any decoraions at all, and what I have found is almost all derogatory.