Residents of Montréal, East, Ward—Quartier — Sub-district D, surnames O (1881 Census)
| # | Surname | Given | Sex | Age | Religion | Origin | Birthplace | Occupation | HH |
| 4 | obrien | helen | F | 75 | Roman Catholic | Irish | Ireland | No Occupation Listed | 12 |
| 25 | obrien | mary | F | 38 | Roman Catholic | Irish | Ireland | No Occupation Listed | 257 |
| 2 | obrien | may | F | 19 | Roman Catholic | Irish | Quebec | No Occupation Listed | 257 |
| 1 | obrien | william | M | 13 | Roman Catholic | Irish | Quebec | No Occupation Listed | 257 |
| 11 | odea | catherine | F | 28 | Roman Catholic | Irish | Quebec | Dressmakers | 305 |
| 12 | odea | james | M | 30 | Roman Catholic | Irish | Quebec | No Occupation Listed | 305 |
| 18 | olivier | albina | F | 10 | Roman Catholic | French | Quebec | No Occupation Listed | 576 |
| 16 | olivier | cuthbert | M | 36 | Roman Catholic | French | Quebec | Conductors, nfs | 576 |
| 19 | olivier | jeffray | M | 7 | Roman Catholic | French | Quebec | No Occupation Listed | 576 |
| 11 | olivier | julie | F | 28 | Roman Catholic | French | Quebec | Dressmakers | 450 |
| 17 | olivier | louisa | F | 27 | Roman Catholic | French | Quebec | No Occupation Listed | 576 |
| 10 | olivier | marie | F | 64 | Roman Catholic | French | Quebec | No Occupation Listed | 450 |
| 2 | orien | adeline | F | 50 | Roman Catholic | French | Quebec | No Occupation Listed | 243 |
| 7 | orien | albertine | F | 6 | Roman Catholic | Irish | Quebec | No Occupation Listed | 243 |
| 8 | orien | arthur | M | 3 | Roman Catholic | Irish | Quebec | No Occupation Listed | 243 |
| 4 | orien | j | M | 11 | Roman Catholic | Irish | Quebec | No Occupation Listed | 243 |
| 1 | orien | james | M | 50 | Roman Catholic | Irish | Ireland | Dealer, merchant etc. (Wholesale & retail trade) | 243 |
| 3 | orien | james | M | 12 | Roman Catholic | Irish | Quebec | No Occupation Listed | 243 |
| 6 | orien | joseph | M | 6 | Roman Catholic | Irish | Quebec | No Occupation Listed | 243 |
| 5 | orien | wilfrid | M | 8 | Roman Catholic | Irish | Quebec | No Occupation Listed | 243 |
| 9 | oshea | annie | F | 18 | Roman Catholic | Irish | United States | No Occupation Listed | 40 |
| 11 | oshea | francis | F | 14 | Roman Catholic | Irish | United States | No Occupation Listed | 40 |
| 6 | oshea | john | M | 48 | Roman Catholic | Irish | Nova Scotia | Drivers (general haulage) | 40 |
| 10 | oshea | john | M | 16 | Roman Catholic | Irish | United States | Salespeople, wholesale or retail trade | 40 |
| 7 | oshea | mary | F | 47 | Roman Catholic | Irish | Ireland | No Occupation Listed | 40 |
| 8 | oshea | mary | F | 20 | Roman Catholic | Irish | United States | No Occupation Listed | 40 |
| 12 | oshea | patrick | M | 11 | Roman Catholic | Irish | Quebec | No Occupation Listed | 40 |
| 4 | ostigney | louis | M | 34 | Roman Catholic | French | Quebec | Bank tellers | 473 |
| 5 | ouellette | alfred | M | 16 | Roman Catholic | French | Quebec | No Occupation Listed | 268 |
| 3 | ouellette | anna | F | 19 | Roman Catholic | French | Quebec | No Occupation Listed | 268 |
| 9 | ouellette | bernadette | F | 5 | Roman Catholic | French | Quebec | No Occupation Listed | 268 |
| 6 | ouellette | caroline | F | 12 | Roman Catholic | French | Quebec | No Occupation Listed | 268 |
| 4 | ouellette | clara | F | 15 | Roman Catholic | French | Quebec | No Occupation Listed | 268 |
| 9 | ouellette | claudia | F | 22 | Roman Catholic | French | Quebec | No Occupation Listed | 258 |
| 2 | ouellette | eleonore | F | 39 | Roman Catholic | French | Quebec | No Occupation Listed | 268 |
| 10 | ouellette | elisabeth | F | 3 | Roman Catholic | French | Quebec | No Occupation Listed | 268 |
| 16 | ouellette | emma | F | 21 | Roman Catholic | French | Quebec | Servants nfs | 473 |
| 1 | ouellette | jean | M | 49 | Roman Catholic | French | Quebec | Washing and laundry services | 268 |
| 11 | ouellette | joseph | M | 0 | Roman Catholic | French | Quebec | No Occupation Listed | 268 |
| 8 | ouellette | marie | F | 7 | Roman Catholic | French | Quebec | No Occupation Listed | 268 |
| 2 | ouellette | marie | F | 25 | Roman Catholic | French | Quebec | Servants nfs | 473 |
| 7 | ouellette | ozilda | F | 9 | Roman Catholic | French | Quebec | No Occupation Listed | 268 |
| 2 | ouimet | adelaide | F | 36 | Roman Catholic | French | Quebec | No Occupation Listed | 580 |
| 1 | ouimet | adolphe | M | 40 | Roman Catholic | French | Quebec | avocat | 580 |
| 3 | ouimet | adolphe | M | 12 | Roman Catholic | French | Quebec | No Occupation Listed | 580 |
| 5 | ouimet | alphonse | M | 7 | Roman Catholic | French | Quebec | No Occupation Listed | 580 |
| 4 | ouimet | eugenie | F | 9 | Roman Catholic | French | Quebec | No Occupation Listed | 580 |
| 9 | ouimet | josephine | F | 18 | Roman Catholic | French | Quebec | Servants nfs | 197 |
| 6 | ouimet | raphael | M | 5 | Roman Catholic | French | Quebec | No Occupation Listed | 580 |
| 7 | ouimet | yvonne | F | 2 | Roman Catholic | French | Quebec | No Occupation Listed | 580 |