O'brien Marriage Records: Groom Firstnames
- Francis (21)
- Francis Boyle (1)
- Francis De Sales (1)
- Francis Edward John (1)
- Francis J (2)
- Francis Leo (1)
- Francis X (1)
- Francis Xavier (1)
- Frank (14)
- Frank M (1)
- Frankie (2)
- Frederick (3)
- Frederick Thomas (1)