Ireland's first recorded St. Patrick's Day Parade took place on March 17, 1975, when the public celebration of this holiday was effectively imported to Ireland from the United States, where St. Patrick's Day parades had been taking place for centuries. Though Irish people were responsible for throwing the first-ever documented St. Patrick's Day parade, this event took place in America during the mid 1700s. At this point, St. Patrick's Day was seen as more of a minor religious holiday than a major national celebration of heritage and identity in Ireland.
This started to change in the early 1900s, when St. Patrick's Day was declared a national Irish holiday in 1903. Even at this point, though, St. Patrick's Day was mostly a quiet family celebration that involved a large meal and religious observance. The holiday's contemporary character, which includes distinctly a religious celebration, consumption of alcohol and public revelry, is mostly an American cultural phenomenon. However, Irish people seem to have happily adopted the practice of throwing public celebrations in recognition of the holiday, including parades.