| O'Brien | Charles | H | of New Kensington | 7 Dec. 1898 | 44y | PA Argus | 14 Dec. 1898 |
| O'Brien | Mrs E J Jr of Latrobe | 6 Sep. 1893 | PA Argus | 13 Aug. 1893 | |||
| O'Connor | Frank | of New Florence | 23 Oct.. 1883 | 22y 2m 0d | Evening Press | 7 Nov. 1883 | |
| O'Connor | Nancy | of near Ludwick, w/o | 11 Jul. 1888 | 40y | PA Argus | 25 Jul. 1888 | |
| O'Donnell | A | A | of Pittsburgh Allegheny Co PA | 16 Jul. 1895 | 41y | PA Argus | 24 Jul. 1895 |
| O'Leary | w/o James of Irwin | 30 Sep. 1897 | 34y | PA Argus | 6 Oct. 1897 | ||
| O'Neil | Bridget | T | 6 Feb. 1869 | 38y | Westmoreland Democrat & PA Argus | 12 Feb. 1869 | |
| O'Neil | John | of New Alexandria | 15 Aug. 1897 | old age | PA Argus | 18 Aug. 1897 | |
| O'Neil | Maria | O | w/o of Scottdale | 21 Apr. 1899 | 65y | PA Argus | 26 Apr. 1899 |
| Ogden | Amos | Col | of Fairfield Twp | 22 Mar. 1867 | 70y | Westmoreland Democrat & PA Argus | 3 Apr. 1867 |
| Ogden | James | S | 17 Jun. 1879 | 40y | Tribune Herald | 27 Jun. 1879 | |
| Ogden | John | H | of Blairsville Indiana Co. PA | 21 Mar. 1899 | 24y | PA Argus | 29 Mar. 1899 |
| Ohms | w/o William of Mt Pleasant | 28 Dec. 1897 | 55y | PA Argus | 5 Jan. 1898 | ||
| Oliphant | Mary | formerly of Uniontown Fayette Co d Trenton NJ w/o S D Oliphant | 15 Oct. 1875 | Tribune Herald | 19 Oct. 1875 | ||
| Olson | Peter | of Irwin | 10 Jun. 1896 | old resident | PA Argus | 17 Jun. 1896 | |
| Olson | w/o Peter, who preceded her in death 6 mos | 3 Jan. 1897 | 59y | PA Argus | 13 Jan. 1897 | ||
| Oplinger | W | H | of Arona | 14 Oct. 1893 | PA Argus | 18 Oct. 1893 | |
| Orr | w/o Clark of Bolivar | 1896 | 23y | PA Argus | 6 May. 1896 | ||
| Orr | Ellen | of Fairfield Twp w/o Robert Orr Esq | 25 Feb.. 1876 | 65y | Tribune Herald | 14 Mar. 1876 | |
| Orr | John | of West Newton | 11 Jun. 1897 | 74y | PA Argus | 16 Jun. 1897 | |
| Orr | Margaret | w/o James Orr of Derry | 12 Feb. 1897 | 46y | PA Argus | 17 Feb. 1897 | |
| Osborne | John | of Irwin | 3 Jan. 1888 | 88y | PA Argus | 11 Jan.. 1888 | |
| Osborne | w/o John | 2 Jan. 1897 | 45y | PA Argus | 13 Jan. 1897 | ||
| Osborne | Maggie | Jane | of Irwin w/o John Osborne d/o Robert Howell | 19 Feb. 1896 | 21y | PA Argus | 26 Feb. 1896 |
| Osborne | Robert | of Parnassus | 26 Sep. 1897 | 81y | PA Argus | 6 Oct. 1897 | |
| Osborne | w/o Robert of Latrobe | 4 Sep. 1899 | PA Argus | 6 Sep. 1899 | |||
| Osier | Joseph | of Tarrs | 2 Apr. 1896 | 83y | PA Argus | 8 Apr. 1896 | |
| Osler | Elizabeth | of near Ruffsdale | 8 Feb. 1887 | 80y | PA Argus | 9 Feb. 1887 | |
| Oursler | Susanna | w/o Henry Oursler Esq of Latrobe | 28 Feb. 1891 | 77y | PA Argus | 4 Mar. 1891 | |
| Ourus | D | of Sewickley | 17 Dec. 1894 | PA Argus | 26 Dec. 1894 | ||
| Over | William | of Irwin | 18 Nov. 1896 | 71y | PA Argus | 25 Nov. 1896 | |
| Overcash | Michael | of Ligonier Valley | 3 Feb. 1873 | 77y 10m 11d | Tribune Herald | 11 Feb. 1873 | |
| Overholt | Abigail | w/o late Henry Overholt who d 30 y ago | 29 Aug. 1898 | 75y | PA Argus | 31 Aug. 1898 | |
| Overhort | Maria | w/o late Abraham Overholt of West Overton | 1 Nov. 1874 | 84y | Tribune Herald | 3 Nov. 1874 | |
| Overholt | Maria | S | of Pittsburgh Allegheny Co PA w/o M S Overholt d/o late Rev Samuel Wakefield | 19 Jun. 1896 | PA Argus | 24 Jun. 1896 | |
| Overly | Catherine | of Ridgeview (Mt Pleasant Twp) w/o | 3 Feb. 1884 | 85y 4m 21d | PA Argus | 13 Feb. 1884 | |
| Overly | David | K | of Irwin | 4 Nov. 1891 | 31y 2m 10d | PA Argus | 11 Nov. 1891 |
| Overly | Elizabeth | of Ridgeview (Mt Pleasant Twp) w/o | 17 Nov. 1885 | 66y 8m 21d | Westmoreland Democrat & PA Argus | 25 Nov. 1885 | |
| Overly | Frank | S | 6 Jul. 1887 | 23y 5m 11d | PA Argus | 16 Jul. 1887 | |
| Overly | George | of Ludwick | 15 Jul. 1875 | 68y | Tribune Herald | 10 Aug. 1875 | |
| Overly | Henry | of Mt Pleasant | 1 Jun.. 1898 | 50y | PA Argus | 8 Jun. 1898 | |
| Overly | John | A | of near Kecksburg | 12 Sep. 1892 | 73y 4m 16d | PA Argus | 21 Sep. 1892 |
| Overly | Lavina | of United w/o George Overly | 21 Aug. 1895 | 63y | PA Argus | 4 Sep. 1895 | |
| Overly | Levi | B | of Scottdale | 28 May. 1898 | 30y | PA Argus | 1 Jun. 1898 |
| Overtusky | James | 8 Jul. 1897 | PA Argus | 14 Jul. 1897 | |||
| Owens | Harry | formerly of Delmont d Apollo Armstrong Co PA | 30 Apr. 1899 | PA Argus | 3 May. 1899 | ||
| Owens | Lazarus | of Washington Twp | 16 Feb. 1896 | 76y | PA Argus | 26 Feb. 1896 | |
| Owens | w/o Patrick of Scottdale | 9 may. 1897 | 25y | PA Argus | 12 May. 1897 | ||
| Oyler | Joseph | of Franklin Twp | 5 Apr. 1873 | 35y | Tribune Herald | 15 Apr. 1873 |
Westmoreland County, PA