Index: Papers of John Adams, Volume 18, O
- O’Bryen, Capt. Richard (of the Dauphin)
- Oglethorpe, Elizabeth Wright (wife of James)
- Oglethorpe, Gen. James (founder of Ga.)
- Ohio Company of Associates
- Old House (Peacefield, now Adams National Historical Park)
- Olive Branch Petition (1775)
- Olive oil
- Oran, Algeria
- Orangists
- O’Reilly, Alexander (Alejandro), Conde (gov. of Cádiz and commander in chief of Andalusia)
- Osborn, William (keeper of Adelphi Hotel, London)
- Osgood, Mary Bowne Franklin (wife of Samuel)
- Osgood, Samuel (Mass. politician)
- Ostend, Belgium
- Osterley Park (Brit. estate)
- Oswald, Richard (Brit. peace negotiator)
- Otis, Col. James (1702–1778)
- Otis, James, Jr. (the Patriot)
- Otis, Joseph (Boston merchant)
- Otis, Samuel Allyne (Boston merchant)
- Otis family
- Otto, Louis Guillaume (French chargé d’affaires in U.S.)
- Ottoman Empire (Sublime Porte)
- Overijssel (province of the Netherlands)
- Oxfordshire, England