St. Patrick's Day is celebrated annually on March 17 in honor of Ireland's patron saint. St. Patrick was born between 370 and 390 C. E. in the Roman Empire in Britain. His given name (Magonus Sucatus or Maewyn Succat) was changed to Patricius (Patrick) either after his baptism or after he became a priest. At the age of 16, Patrick was kidnapped and sold into slavery in Ireland. He remained in captivity for six years during which time he worked as a shepherd and began to have religious visions. During one of the visions, Patrick became aware of a rescue ship and he fled to France.
Patrick eventually returned to Ireland as a missionary and succeeded in converting the Irish to Christianity. He used a shamrock to explain the Trinity to potential converts. The three leaves of the shamrock represented the father, son, and holy spirit. Patrick is also reported to have driven all of the snakes, a pagan symbol, out of Ireland and into the sea where they drowned. This is perhaps a metaphor for driving paganism out of Ireland since biologists believe there were no snakes in Ireland at the time.
St. Patrick's Day celebrations in the United States are secular and date back as far as 1737 when Boston held its first St. Patrick's Day parade. The day is celebrated with green beer, the wearing of green clothing, and parades. However, in Ireland, the day is primarily a religious occasion.
Because many Americans celebrate their Irish lineage on St. Patrick's Day, March was chosen as Irish American Heritage Month. The month was proclaimed in 1995 by Congress (Public Law 103-379).