Complex sentence: Born in Tucson, O'Dunne was the son Judge Edmund F. Dunne, who was Chief Justice of the Arizona Territory at the time, and Josephine Cecelia Warner who, though originally from Mississippi herself, was part of an old Virginia family.
Split into simpler sentences: Born in Tucson, O'Dunne was the son Judge Edmund F. Dunne, who was Chief Justice of the Arizona Territory at the time. His mother Josephine Cecelia Warner, though originally from Mississippi herself, was part of an old Virginia family.