Patrick wasn't Irish. He was actually British, and he was taken captive and brought to Ireland, where he was a prisoner for 6 years. After that, he returned home to England for religious training. He did eventually make his way back to Ireland.
A family retells the story of the shillelagh that was whittled from a tree. During the Irish potato famine, Fergus and his family left for America. But first Fergus cut a branch from a blackthorn tree to take a piece of Ireland with him.