| Surname | Individuals |
|---|---|
|
O'Brien
|
2 |
|
O'Connor
|
7 |
|
O'Daniell
|
1 |
|
O'Donnell
|
1 |
|
O'Farrell
|
3 |
|
O'Grady
|
1 |
|
O'Killea
|
1 |
|
O'Killey
|
16 |
|
O'Meara
|
1 |
|
Oakes
|
3 |
|
Oakley
|
1 |
|
Oakman
|
21 |
|
Oaks
|
1 |
|
Oatman
|
2 |
|
Oddbj÷rg
|
1 |
|
Olar
|
1 |
|
Oldham
|
2 |
|
Olds
|
3 |
|
Olin
|
5 |
|
Oliver
|
2 |
|
Olla
|
1 |
|
Ollyver
|
1 |
|
Olsen
|
11 |
|
Olson
|
1 |
|
Olveet
|
1 |
|
Ooman
|
3 |
|
Orcutt
|
1 |
|
Orhmunth
|
3 |
|
Orlando
|
1 |
|
Ormon
|
1 |
|
Orne
|
2 |
|
Orr
|
1 |
|
Ortner
|
2 |
|
Osborn
|
3 |
|
Ostrander
|
4 |
|
Oswald
|
11 |
|
Otis
|
5 |
|
Ott
|
1 |
|
Outlaw
|
1 |
|
Ovenshire
|
1 |
|
Owen
|
2 |
|
Owens
|
1 |