Residents of Flamborough W-O — Sub-district C, surnames O (1881 Census)
| # | Surname | Given | Sex | Age | Religion | Origin | Birthplace | Occupation | HH |
| 10 | obrien | bridget | F | 7 | Roman Catholic | Irish | Ontario | No Occupation Listed | 284 |
| 12 | obrien | john | M | 4 | Roman Catholic | Irish | Ontario | No Occupation Listed | 284 |
| 25 | obrien | lucy | F | 78 | Anglican | Irish | Ireland | No Occupation Listed | 605 |
| 9 | obrien | mary | F | 35 | Roman Catholic | Irish | Ireland | Hotel Keepers and Managers | 284 |
| 11 | obrien | mary | F | 5 | Roman Catholic | Irish | Ontario | No Occupation Listed | 284 |
| 20 | obrien | thomas | M | 32 | Anglican | Irish | Ireland | Labourers nfs | 605 |
| 2 | oconnell | agnes | F | 0 | Roman Catholic | Irish | Ontario | No Occupation Listed | 177 |
| 9 | oconnell | ann | F | 70 | Roman Catholic | Irish | Ireland | No Occupation Listed | 174 |
| 23 | oconnell | hugh | M | 9 | Roman Catholic | Irish | Ontario | No Occupation Listed | 116 |
| 1 | oconnell | hugh | M | 2 | Roman Catholic | Irish | Ontario | No Occupation Listed | 177 |
| 20 | oconnell | john | M | 39 | Roman Catholic | Irish | Ontario | Farmers, general and nfs | 116 |
| 22 | oconnell | john | M | 10 | Roman Catholic | Irish | Ontario | No Occupation Listed | 116 |
| 21 | oconnell | margret | F | 36 | Roman Catholic | Irish | Ontario | No Occupation Listed | 116 |
| 8 | oconnell | mary | F | 28 | Roman Catholic | Irish | Ontario | No Occupation Listed | 174 |
| 25 | oconnell | mary | F | 30 | Roman Catholic | Irish | Ontario | No Occupation Listed | 177 |
| 24 | oconnell | michael | M | 2 | Roman Catholic | Irish | Ontario | No Occupation Listed | 116 |
| 7 | oconnell | owen | M | 35 | Roman Catholic | Irish | Ontario | Farmers, general and nfs | 174 |
| 24 | oconnell | pat | M | 34 | Roman Catholic | Irish | Ontario | Farmers, general and nfs | 177 |
| 5 | oconnner | lilly | F | 15 | Anglican | Irish | Ontario | Servants nfs | 309 |
| 12 | oconnor | charles | M | 7 | Roman Catholic | Irish | Ontario | No Occupation Listed | 48 |
| 5 | oconnor | frances | F | 42 | Roman Catholic | Irish | Ontario | No Occupation Listed | 48 |
| 13 | oconnor | francic | M | 6 | Roman Catholic | Irish | Ontario | No Occupation Listed | 48 |
| 11 | oconnor | jerome | M | 9 | Roman Catholic | Irish | Ontario | No Occupation Listed | 48 |
| 10 | oconnor | joseph | M | 12 | Roman Catholic | Irish | Ontario | No Occupation Listed | 48 |
| 15 | oconnor | louisa | F | 2 | Roman Catholic | Irish | Ontario | No Occupation Listed | 48 |
| 6 | oconnor | mary | F | 18 | Roman Catholic | Irish | Ontario | No Occupation Listed | 48 |
| 9 | oconnor | peter | M | 14 | Roman Catholic | Irish | Ontario | No Occupation Listed | 48 |
| 8 | oconnor | sarah | F | 15 | Roman Catholic | Irish | Ontario | No Occupation Listed | 48 |
| 7 | oconnor | vincent | M | 17 | Roman Catholic | Irish | Ontario | Farmers, general and nfs | 48 |
| 14 | oconnor | william | M | 4 | Roman Catholic | Irish | Ontario | No Occupation Listed | 48 |
| 4 | oconor | michael | M | 36 | Roman Catholic | Irish | Ontario | Farmers, general and nfs | 48 |
| 3 | odea | john | M | 12 | Roman Catholic | Irish | Nova Scotia | Servants nfs | 333 |
| 21 | oliver | mary | F | 15 | Anglican | Scottish | Ontario | Servants nfs | 683 |
| 7 | onalley | catherine | F | 58 | Roman Catholic | Irish | Ireland | No Occupation Listed | 132 |
| 11 | onalley | catherine | F | 18 | Roman Catholic | Irish | Ontario | No Occupation Listed | 132 |
| 8 | onalley | hugh | M | 25 | Roman Catholic | Irish | Scotland | Labourers nfs | 132 |
| 6 | onalley | john | M | 67 | Roman Catholic | Irish | Ireland | Labourers nfs | 131 |
| 9 | onalley | mary | F | 23 | Roman Catholic | Irish | Ontario | No Occupation Listed | 132 |
| 10 | onalley | richard | M | 21 | Roman Catholic | Irish | Ontario | Labourers nfs | 132 |
| 24 | orielly | clara | F | 4 | Roman Catholic | Irish | Ontario | No Occupation Listed | 281 |
| 21 | orielly | duncan | M | 7 | Methodist | Scottish | Ontario | No Occupation Listed | 255 |
| 23 | orielly | edward | M | 6 | Roman Catholic | Irish | Ontario | No Occupation Listed | 281 |
| 25 | orielly | george | M | 6 | Methodist | Irish | Ontario | No Occupation Listed | 256 |
| 20 | orielly | isabella | F | 62 | Methodist | Irish | Ontario | No Occupation Listed | 255 |
| 21 | orielly | jacob | M | 9 | Roman Catholic | Irish | Ontario | No Occupation Listed | 281 |
| 1 | orielly | james | M | 0 | Methodist | Irish | Ontario | No Occupation Listed | 256 |
| 24 | orielly | john | M | 9 | Methodist | Irish | Ontario | No Occupation Listed | 256 |
| 18 | orielly | john | M | 35 | Roman Catholic | Irish | Ireland | Labourers nfs | 281 |
| 25 | orielly | julia | F | 2 | Roman Catholic | Irish | Ontario | No Occupation Listed | 281 |
| 23 | orielly | june | F | 30 | Methodist | German | Ontario | No Occupation Listed | 256 |
| 19 | orielly | kate | F | 40 | Roman Catholic | German | Germany | No Occupation Listed | 281 |
| 20 | orielly | louisa | F | 14 | Roman Catholic | Irish | Ontario | No Occupation Listed | 281 |
| 22 | orielly | patrick | M | 34 | Methodist | Irish | Ontario | Farmers, general and nfs | 256 |
| 22 | orielly | patrick | M | 6 | Roman Catholic | Irish | Ontario | No Occupation Listed | 281 |
| 19 | orielly | william | M | 71 | Methodist | Irish | Ontario | Farmers, general and nfs | 255 |
| 17 | orourk | margret | F | 64 | Roman Catholic | Irish | Ireland | No Occupation Listed | 330 |
| 16 | orourk | michael | M | 66 | Roman Catholic | Irish | Ireland | Labourers nfs | 330 |
| 17 | orr | emma | F | 3 | Methodist | Irish | Ontario | No Occupation Listed | 196 |
| 23 | orr | ethel | F | 1 | Methodist | Irish | Ontario | No Occupation Listed | 312 |
| 16 | orr | harriet | F | 7 | Methodist | Irish | Ontario | No Occupation Listed | 196 |
| 21 | orr | john | M | 31 | Methodist | Irish | Ontario | Farmers, general and nfs | 312 |
| 22 | orr | margret | F | 19 | Methodist | Dutch | Ontario | No Occupation Listed | 312 |
| 14 | orr | mary | F | 33 | Methodist | English | Ontario | No Occupation Listed | 196 |
| 15 | orr | thos | M | 9 | Methodist | Irish | Ontario | No Occupation Listed | 196 |
| 13 | orr | william | M | 37 | Methodist | Irish | Ontario | Carpenters | 196 |
| 18 | orr | william | M | 0 | Methodist | Irish | Ontario | No Occupation Listed | 196 |