Residents of Nepean — Sub-district A, surnames O (1881 Census)
| # | Surname | Given | Sex | Age | Religion | Origin | Birthplace | Occupation | HH |
| 1 | obrein | catherine | F | 15 | Wesleyan Methodist | Irish | Ontario | No Occupation Listed | 106 |
| 10 | obrien | agnes | F | 43 | Wesleyan Methodist | Irish | Quebec | No Occupation Listed | 474 |
| 6 | obrien | bridget | F | 25 | Roman Catholic | Irish | Ontario | No Occupation Listed | 125 |
| 6 | obrien | edward | M | 1 | Roman Catholic | Irish | Ontario | No Occupation Listed | 604 |
| 3 | obrien | eliza | F | 7 | Roman Catholic | Irish | Ontario | No Occupation Listed | 604 |
| 4 | obrien | henry | M | 28 | Roman Catholic | Irish | Ontario | No Occupation Listed | 125 |
| 24 | obrien | james | M | 16 | Roman Catholic | Irish | England | No Occupation Listed | 604 |
| 21 | obrien | john | M | 37 | Roman Catholic | Irish | Ireland | Labourers nfs | 604 |
| 23 | obrien | john | M | 18 | Roman Catholic | Irish | England | No Occupation Listed | 604 |
| 9 | obrien | julia | F | 19 | Roman Catholic | Irish | Ontario | No Occupation Listed | 125 |
| 10 | obrien | laban | M | 22 | Anglican | Irish | Ireland | Labourers nfs | 43 |
| 7 | obrien | lena | F | 24 | Roman Catholic | Irish | Ontario | No Occupation Listed | 125 |
| 5 | obrien | maggie | F | 26 | Roman Catholic | Irish | Ontario | No Occupation Listed | 125 |
| 4 | obrien | margaret | F | 5 | Roman Catholic | Irish | Ontario | No Occupation Listed | 604 |
| 3 | obrien | mary | F | 60 | Roman Catholic | Irish | Ireland | No Occupation Listed | 125 |
| 22 | obrien | mary | F | 27 | Roman Catholic | Irish | Ireland | No Occupation Listed | 604 |
| 2 | obrien | mary | F | 8 | Roman Catholic | Irish | Ontario | No Occupation Listed | 604 |
| 10 | obrien | michael | M | 18 | Roman Catholic | Irish | Ontario | No Occupation Listed | 125 |
| 25 | obrien | patrick | M | 13 | Roman Catholic | Irish | England | No Occupation Listed | 604 |
| 8 | obrien | sarah | F | 22 | Roman Catholic | Irish | Ontario | No Occupation Listed | 125 |
| 1 | obrien | thomas | M | 11 | Roman Catholic | Irish | Ontario | No Occupation Listed | 604 |
| 5 | obrien | william | M | 3 | Roman Catholic | Irish | Ontario | No Occupation Listed | 604 |
| 11 | ocomor | helen | F | 40 | Roman Catholic | Scottish | Ireland | No Occupation Listed | 194 |
| 13 | oconnell | margret | F | 60 | Roman Catholic | Irish | Ireland | No Occupation Listed | 383 |
| 14 | oconnell | michael | M | 21 | Roman Catholic | Irish | United States | No Occupation Listed | 383 |
| 21 | odonnell | michael | M | 25 | Roman Catholic | Irish | Ontario | Saddler and harness maker | 180 |
| 7 | ogarra | alice | F | 13 | Roman Catholic | Irish | Ontario | No Occupation Listed | 750 |
| 9 | ogarra | catherine | F | 7 | Roman Catholic | Irish | Ontario | No Occupation Listed | 750 |
| 12 | ogarra | charles | M | 1 | Roman Catholic | Irish | Ontario | No Occupation Listed | 750 |
| 8 | ogarra | edward | M | 10 | Roman Catholic | Irish | Ontario | No Occupation Listed | 750 |
| 11 | ogarra | francis | M | 3 | Roman Catholic | Irish | Ontario | No Occupation Listed | 750 |
| 10 | ogarra | james | M | 5 | Roman Catholic | Irish | Ontario | No Occupation Listed | 750 |
| 6 | ogarra | john | M | 16 | Roman Catholic | Irish | Ontario | No Occupation Listed | 750 |
| 5 | ogarra | margaret | F | 36 | Roman Catholic | Irish | Ontario | No Occupation Listed | 750 |
| 4 | ogarra | martin | M | 43 | Roman Catholic | Irish | Ireland | Judges | 750 |
| 14 | ogrady | ann | F | 5 | Roman Catholic | Irish | Ontario | No Occupation Listed | 137 |
| 8 | ogrady | ann | F | 40 | Roman Catholic | Irish | Ontario | No Occupation Listed | 66 |
| 13 | ogrady | ann | F | 29 | Roman Catholic | Irish | Ontario | Servants nfs | 187 |
| 3 | ogrady | anne | F | 0 | Roman Catholic | Irish | Ireland | No Occupation Listed | 141 |
| 11 | ogrady | anney | F | 25 | Roman Catholic | Irish | Ontario | No Occupation Listed | 35 |
| 23 | ogrady | augusta | F | 0 | Roman Catholic | Irish | Ontario | No Occupation Listed | 126 |
| 2 | ogrady | bridget | F | 13 | Roman Catholic | Irish | Ontario | No Occupation Listed | 278 |
| 11 | ogrady | catherin | F | 23 | Roman Catholic | Irish | Ontario | No Occupation Listed | 2 |
| 23 | ogrady | catherin | F | 43 | Roman Catholic | Irish | Ontario | No Occupation Listed | 68 |
| 25 | ogrady | catherin | F | 29 | Roman Catholic | Irish | Ontario | No Occupation Listed | 141 |
| 25 | ogrady | charles | M | 19 | Roman Catholic | Irish | Ontario | Farmers, general and nfs | 68 |
| 6 | ogrady | daniel | M | 39 | Roman Catholic | Irish | Ontario | Farmers, general and nfs | 22 |
| 4 | ogrady | eliza | F | 0 | Roman Catholic | Irish | Ontario | No Occupation Listed | 164 |
| 9 | ogrady | elizabeth | F | 35 | Roman Catholic | Irish | Ontario | No Occupation Listed | 2 |
| 10 | ogrady | elizabeth | F | 28 | Roman Catholic | Irish | Ontario | No Occupation Listed | 2 |
| 21 | ogrady | elizabeth | F | 6 | Roman Catholic | Irish | Ontario | No Occupation Listed | 67 |
| 18 | ogrady | ellen | F | 12 | Roman Catholic | Irish | Ontario | No Occupation Listed | 67 |
| 20 | ogrady | hannah | F | 8 | Roman Catholic | Irish | Ontario | No Occupation Listed | 67 |
| 3 | ogrady | helen | F | 6 | Roman Catholic | Irish | Ontario | No Occupation Listed | 278 |
| 12 | ogrady | henry | M | 35 | Roman Catholic | Irish | Ontario | Farmers, general and nfs | 137 |
| 2 | ogrady | henry | M | 85 | Roman Catholic | Irish | Ireland | Farmers, general and nfs | 21 |
| 25 | ogrady | james | M | 17 | Roman Catholic | Irish | Ontario | No Occupation Listed | 278 |
| 24 | ogrady | james | M | 80 | Roman Catholic | Irish | Ireland | No Occupation Listed | 126 |
| 3 | ogrady | james | M | 2 | Roman Catholic | Irish | Ontario | No Occupation Listed | 164 |
| 10 | ogrady | james | M | 29 | Roman Catholic | Irish | Ontario | Farmers, general and nfs | 35 |
| 7 | ogrady | james | M | 53 | Roman Catholic | Irish | Quebec | Farmers, general and nfs | 66 |
| 2 | ogrady | james | M | 15 | Roman Catholic | Irish | Ontario | No Occupation Listed | 68 |
| 4 | ogrady | jane | F | 11 | Roman Catholic | Irish | Ontario | No Occupation Listed | 68 |
| 18 | ogrady | john | M | 45 | Roman Catholic | Irish | Ontario | Hotel Keepers and Managers | 126 |
| 8 | ogrady | john | M | 42 | Roman Catholic | Irish | Ontario | Farmers, general and nfs | 2 |
| 1 | ogrady | john | M | 45 | Roman Catholic | Irish | Ontario | Farmers, general and nfs | 21 |
| 10 | ogrady | john | M | 56 | Roman Catholic | Irish | Ireland | Farmers, general and nfs | 67 |
| 19 | ogrady | john | M | 11 | Roman Catholic | Irish | Ontario | No Occupation Listed | 67 |
| 4 | ogrady | judy | F | 77 | Roman Catholic | Irish | Ireland | No Occupation Listed | 22 |
| 20 | ogrady | julia | F | 8 | Roman Catholic | Irish | Ontario | No Occupation Listed | 126 |
| 16 | ogrady | julia | F | 1 | Roman Catholic | Irish | Ontario | No Occupation Listed | 137 |
| 17 | ogrady | julia | F | 14 | Roman Catholic | Irish | Ontario | No Occupation Listed | 67 |
| 6 | ogrady | julia | F | 7 | Roman Catholic | Irish | Ontario | No Occupation Listed | 68 |
| 1 | ogrady | julia | F | 3 | Roman Catholic | Irish | Ontario | No Occupation Listed | 141 |
| 4 | ogrady | julia | F | 71 | Roman Catholic | Irish | Ireland | No Occupation Listed | 141 |
| 23 | ogrady | margaret | F | 41 | Roman Catholic | Irish | Ireland | No Occupation Listed | 278 |
| 19 | ogrady | margaret | F | 41 | Roman Catholic | Irish | Ontario | No Occupation Listed | 126 |
| 13 | ogrady | margaret | F | 32 | Roman Catholic | Scottish | Ontario | No Occupation Listed | 137 |
| 15 | ogrady | margaret | F | 3 | Roman Catholic | Irish | Ontario | No Occupation Listed | 137 |
| 2 | ogrady | margaret | F | 3 | Roman Catholic | Irish | Ontario | No Occupation Listed | 164 |
| 1 | ogrady | margret | F | 14 | Roman Catholic | Irish | Ontario | No Occupation Listed | 278 |
| 12 | ogrady | margret | F | 22 | Roman Catholic | Irish | Ontario | No Occupation Listed | 67 |
| 24 | ogrady | mary | F | 19 | Roman Catholic | Irish | Quebec | No Occupation Listed | 278 |
| 21 | ogrady | mary | F | 5 | Roman Catholic | Irish | Ontario | No Occupation Listed | 126 |
| 1 | ogrady | mary | F | 22 | Roman Catholic | Irish | Ontario | No Occupation Listed | 164 |
| 5 | ogrady | mary | F | 42 | Roman Catholic | Irish | Ontario | No Occupation Listed | 22 |
| 11 | ogrady | mary | F | 49 | Roman Catholic | Irish | Ontario | No Occupation Listed | 67 |
| 13 | ogrady | mary | F | 21 | Roman Catholic | Irish | Ontario | No Occupation Listed | 67 |
| 1 | ogrady | mary | F | 17 | Roman Catholic | Irish | Ontario | No Occupation Listed | 68 |
| 5 | ogrady | mary | F | 25 | Roman Catholic | Irish | Ontario | No Occupation Listed | 141 |
| 22 | ogrady | michael | M | 40 | Roman Catholic | Irish | Ireland | Labourers nfs | 278 |
| 9 | ogrady | michel | M | 16 | Roman Catholic | Irish | Ontario | No Occupation Listed | 66 |
| 14 | ogrady | michel | M | 20 | Roman Catholic | Irish | Ontario | No Occupation Listed | 67 |
| 24 | ogrady | michel | M | 21 | Roman Catholic | Irish | Ontario | Farmers, general and nfs | 68 |
| 15 | ogrady | patrick | M | 18 | Roman Catholic | Irish | Ontario | No Occupation Listed | 67 |
| 24 | ogrady | patrick | M | 42 | Roman Catholic | Irish | Ontario | Farmers, general and nfs | 141 |
| 12 | ogrady | roderick | M | 22 | Roman Catholic | Irish | Ontario | No Occupation Listed | 2 |
| 3 | ogrady | simon | M | 37 | Roman Catholic | Irish | Ontario | Farmers, general and nfs | 22 |
| 16 | ogrady | simon | M | 16 | Roman Catholic | Irish | Ontario | No Occupation Listed | 67 |
| 5 | ogrady | simon | M | 9 | Roman Catholic | Irish | Ontario | No Occupation Listed | 68 |
| 2 | ogrady | teresa | F | 2 | Roman Catholic | Irish | Ontario | No Occupation Listed | 141 |
| 22 | ogrady | theresa | F | 2 | Roman Catholic | Irish | Ontario | No Occupation Listed | 126 |
| 22 | ogrady | thomas | M | 57 | Roman Catholic | Irish | Ireland | Farmers, general and nfs | 68 |
| 3 | ogrady | thomas | M | 13 | Roman Catholic | Irish | Ontario | No Occupation Listed | 68 |
| 25 | ogrady | timothy | M | 35 | Roman Catholic | Irish | Ontario | Farmers, general and nfs | 164 |
| 12 | ogrady | victoria | F | 2 | Roman Catholic | Irish | Ontario | No Occupation Listed | 35 |
| 17 | ohara | annie | F | 30 | Roman Catholic | Irish | Ontario | No Occupation Listed | 56 |
| 20 | ohara | edith | F | 3 | Roman Catholic | Irish | Ontario | No Occupation Listed | 56 |
| 16 | ohara | george | M | 31 | Roman Catholic | Irish | Ontario | Labourers nfs | 56 |
| 21 | ohara | john | M | 1 | Roman Catholic | Irish | Ontario | No Occupation Listed | 56 |
| 18 | ohara | lissie | F | 8 | Roman Catholic | Irish | Ontario | No Occupation Listed | 56 |
| 19 | ohara | thomas | M | 5 | Roman Catholic | Irish | Ontario | No Occupation Listed | 56 |
| 15 | okeef | ann | F | 53 | Roman Catholic | Irish | Ireland | No Occupation Listed | 188 |
| 23 | okeef | bridget | F | 13 | Roman Catholic | Irish | Ontario | No Occupation Listed | 188 |
| 19 | okeef | corneless | M | 21 | Roman Catholic | Irish | Ontario | No Occupation Listed | 188 |
| 18 | okeef | david | M | 22 | Roman Catholic | Irish | Ontario | No Occupation Listed | 188 |
| 20 | okeef | edward | M | 20 | Roman Catholic | Irish | Ontario | No Occupation Listed | 188 |
| 25 | okeef | hannah | F | 7 | Roman Catholic | Irish | Ontario | No Occupation Listed | 188 |
| 22 | okeef | john | M | 14 | Roman Catholic | Irish | Ontario | No Occupation Listed | 188 |
| 17 | okeef | mary | F | 24 | Roman Catholic | Irish | Ontario | No Occupation Listed | 188 |
| 16 | okeef | michel | M | 26 | Roman Catholic | Irish | Ontario | Farmers, general and nfs | 188 |
| 14 | okeef | paterick | M | 55 | Roman Catholic | Irish | Ontario | Farmers, general and nfs | 188 |
| 21 | okeef | paterick | M | 17 | Roman Catholic | Irish | Ontario | No Occupation Listed | 188 |
| 24 | okeef | william | M | 12 | Roman Catholic | Irish | Ontario | No Occupation Listed | 188 |
| 5 | okelly | david | M | 57 | Roman Catholic | Irish | Ireland | river drivers | 47 |
| 24 | olmested | abraham | M | 7 | Anglican | English | Ontario | No Occupation Listed | 14 |
| 1 | olmested | alexander | M | 0 | Anglican | English | Ontario | No Occupation Listed | 14 |
| 23 | olmested | ester | F | 9 | Anglican | English | Ontario | No Occupation Listed | 14 |
| 22 | olmested | marcy | F | 11 | Anglican | English | Ontario | No Occupation Listed | 14 |
| 20 | olmested | nancy | F | 37 | Anglican | Irish | Ireland | No Occupation Listed | 14 |
| 19 | olmested | solomon | M | 48 | Anglican | English | Ontario | Farmers, general and nfs | 14 |
| 25 | olmested | solomon | M | 2 | Anglican | English | Ontario | No Occupation Listed | 14 |
| 21 | olmested | william | M | 13 | Anglican | English | Ontario | No Occupation Listed | 14 |
| 15 | olmsted | abram | M | 7 | Anglican | English | Ontario | No Occupation Listed | 8 |
| 19 | olmsted | ann | F | 80 | Anglican | English | Ireland | No Occupation Listed | 9 |
| 14 | olmsted | anney | F | 29 | Anglican | Scottish | Ontario | No Occupation Listed | 8 |
| 22 | olmsted | araminta | F | 10 | Methodist | English | Ontario | No Occupation Listed | 10 |
| 13 | olmsted | george | M | 45 | Anglican | English | Ontario | Farmers, general and nfs | 8 |
| 17 | olmsted | george | M | 2 | Anglican | English | Ontario | No Occupation Listed | 8 |
| 18 | olmsted | gideon | M | 56 | Anglican | English | Quebec | No Occupation Listed | 9 |
| 23 | olmsted | lewisa | F | 6 | Methodist | English | Ontario | No Occupation Listed | 10 |
| 20 | olmsted | richard | M | 43 | Methodist | English | Ontario | Farmers, general and nfs | 10 |
| 21 | olmsted | sarah | F | 34 | Methodist | Irish | Ontario | No Occupation Listed | 10 |
| 16 | olmsted | thomas | M | 4 | Anglican | English | Ontario | No Occupation Listed | 8 |
| 1 | omalley | james | M | 61 | Roman Catholic | Irish | Ireland | Contractors (and builders, U.S.) | 455 |
| 2 | omalley | margret | F | 59 | Roman Catholic | Irish | Ireland | No Occupation Listed | 455 |
| 3 | omalley | sarah | F | 17 | Roman Catholic | Irish | Ontario | No Occupation Listed | 455 |
| 3 | omara | ellen | F | 75 | Roman Catholic | Irish | Ireland | No Occupation Listed | 47 |
| 2 | omara | helenna | F | 23 | Roman Catholic | Irish | Ontario | No Occupation Listed | 47 |
| 1 | omara | martin | M | 30 | Roman Catholic | Irish | Ontario | Hotel Keepers and Managers | 47 |
| 4 | omara | mary | F | 53 | Roman Catholic | Irish | Ontario | No Occupation Listed | 47 |
| 7 | omares | elizabeth | F | 43 | Roman Catholic | Irish | Ontario | No Occupation Listed | 39 |
| 8 | omares | jane | F | 18 | Roman Catholic | Irish | Ontario | No Occupation Listed | 39 |
| 6 | omares | patric | M | 60 | Roman Catholic | Irish | Ireland | Teachers (unspecified) | 39 |
| 7 | omarrah | bridget | F | 33 | Roman Catholic | Irish | Ontario | No Occupation Listed | 150 |
| 8 | omarrah | mary | F | 4 | Roman Catholic | Irish | Ontario | No Occupation Listed | 150 |
| 9 | omarrah | michel | M | 3 | Roman Catholic | Irish | Ontario | No Occupation Listed | 150 |
| 6 | omarrah | thomas | M | 38 | Roman Catholic | Irish | Ireland | Farmers, general and nfs | 150 |
| 10 | omarrah | thomas | M | 1 | Roman Catholic | Irish | Ontario | No Occupation Listed | 150 |
| 6 | omera | bridget | F | 38 | Roman Catholic | Irish | Ireland | No Occupation Listed | 43 |
| 10 | omera | bridget | F | 6 | Roman Catholic | Irish | Ontario | No Occupation Listed | 43 |
| 9 | omera | david | M | 9 | Roman Catholic | Irish | Ontario | No Occupation Listed | 43 |
| 11 | omera | james | M | 0 | Roman Catholic | Irish | Ontario | No Occupation Listed | 43 |
| 5 | omera | phillip | M | 40 | Roman Catholic | Irish | Ireland | river drivers | 43 |
| 7 | omera | phillip | M | 13 | Roman Catholic | Irish | Quebec | No Occupation Listed | 43 |
| 8 | omera | wm | M | 10 | Roman Catholic | Irish | Quebec | No Occupation Listed | 43 |
| 18 | oneal | martin | M | 26 | Roman Catholic | Irish | Ontario | No Occupation Listed | 13 |
| 19 | oneil | bridget | F | 60 | Roman Catholic | Irish | Ireland | No Occupation Listed | 13 |
| 20 | oneil | bridget | F | 21 | Roman Catholic | Irish | Ontario | No Occupation Listed | 13 |
| 15 | oneil | catherine | F | 30 | Roman Catholic | Irish | Ireland | No Occupation Listed | 575 |
| 20 | oneil | catherine | F | 9 | Roman Catholic | Irish | Ontario | No Occupation Listed | 575 |
| 16 | oneil | edward | M | 17 | Roman Catholic | Irish | Ontario | No Occupation Listed | 575 |
| 17 | oneil | eliza | F | 15 | Roman Catholic | Irish | Ontario | No Occupation Listed | 575 |
| 23 | oneil | hugh | M | 4 | Roman Catholic | Irish | Ontario | No Occupation Listed | 575 |
| 18 | oneil | margaret | F | 13 | Roman Catholic | Irish | Ontario | No Occupation Listed | 575 |
| 21 | oneil | mary | F | 16 | Roman Catholic | Irish | Ontario | No Occupation Listed | 13 |
| 22 | oneil | mary | F | 5 | Roman Catholic | Irish | Ontario | No Occupation Listed | 575 |
| 14 | oneil | michael | M | 50 | Roman Catholic | Irish | Quebec | Farmers, general and nfs | 575 |
| 19 | oneil | michael | M | 11 | Roman Catholic | Irish | Ontario | No Occupation Listed | 575 |
| 21 | oneil | thomas | M | 7 | Roman Catholic | Irish | Ontario | No Occupation Listed | 575 |
| 6 | onia | amelia | F | 45 | Presbyterian | Swedish | Sweden | Servants nfs | 681 |
| 9 | orange | ellen | F | 28 | Anglican | Irish | Ireland | No Occupation Listed | 75 |
| 11 | orange | georgina | F | 2 | Anglican | Irish | Ontario | No Occupation Listed | 75 |
| 8 | orange | john | M | 39 | Anglican | Irish | Ireland | Toll collectors | 75 |
| 10 | orange | thos | M | 7 | Anglican | Irish | Ontario | No Occupation Listed | 75 |
| 22 | owens | james | M | 35 | Anglican | Irish | Ontario | Farmers, general and nfs | 50 |
| 25 | owens | james | M | 1 | Anglican | Irish | Ontario | No Occupation Listed | 50 |
| 23 | owens | rebeca | F | 32 | Anglican | Irish | Ontario | No Occupation Listed | 50 |
| 24 | owens | robert | M | 4 | Anglican | Irish | Ontario | No Occupation Listed | 50 |