Andrew Avellino was a 16th-century Italian Theatine priest born in Castronuovo di Sant'Andrea. Originally named Lancelotto, he changed his name upon joining his religious order. After studying law in Naples, he served as a lawyer before dedicating himself to ecclesiastical reform and spiritual leadership. He was known for his extensive work in preaching, administering confessions, and caring for the sick. Throughout his ministry, he helped establish several new houses for the Theatine order and acted as a spiritual advisor to influential figures like Charles Borromeo.