Patrick's own letter, the Confessio, records his birth in Roman Britain, his kidnapping by Irish raiders, six years herding as a slave, his escape, and his return as a missionary. He called himself Patricius; the birth name Maewyn Succat appears only in later sources and is contested. March 17 marks his death, year disputed.
The legend of Patrick driving Ireland's snakes into the sea is zoologically impossible: the National Museum of Ireland's Nigel Monaghan confirms there is no fossil or other record of snakes ever living on the island. Readers have long treated the snakes as a metaphor for druids, which is also not in the early sources.
Shamrock Trinity lessons, a 120-year lifespan, staffs growing into trees: the dossier accrued for centuries after his death. The loudest modern version of the holiday, the parade-and-green-beer format, was itself largely an export of the Irish diaspora back to Ireland.
Ireland's patron saint was an imported slave who banished animals that were never there; how much of any national symbol is import and invention?