Not to take anything away from the other patron saint of Ireland, (or even Columba, the other patron) but for this day at least, let's celebrate the only female bishop in the Catholic tradition (or at least the legend says so).
Brigid's mother, Broccha, was the slave of her father, Dubtach. When Dubtach sold Broccha, young Brigid went with her until she was old enough to return to her master's (father's) house. While under her mother's guidance, she was baptized by the bishop of Ireland (the famous one who is the other patron) and later heard him preach.
When she went back to Dubtach's, she was so filled with Christian mercy that she kept giving away his wealth to the poor. When she gave an ancient and expensive sword, a family heirloom, to a leper, Daddy Dubtach would have beaten her, but her explanation that it was given to the Lord through this leper was persuasive -- the King forbade Dubtach to beat her, so he freed her instead, saying that he needed to keep some of his property for himself and she would have given it all away.
Brigid went back to her mom, who was in charge of her master's dairy. The dairy flourished with Brigid's help, but she kept giving out the surplus cream and milk to the poor. The master freed her mother to get Brigid to go -- again, better to have a little and keep it than to have a lot but have it all given to the needy.
There are other legends of her ability as a provider for the poor -- cows that give milk three times a day and a barrel of beer that never runs dry. She was no doubt a significant leader in the Church in her region, whether or not she actually was the bishop or just got to pick the man who held the office. A pre-schism figure, she is venerated in the Eastern tradition as well as the Western.