Authors
- William Orpen 1
- David B. Orr 1
- Adolfo Orsi 1
- Dennis Ortenburger 1
- Hugh Orton 2
- George Orwell 1
- Yotty Osborn 2
- Edgar Osborne 1
- Kevin Osborne 1
- Nancy Cabot Osborne 1
- Susan Osborne 1
- Jonny Osterman 1
- Yvonne Ostroga 1
- Charles W. Ostrom 1
- Werner Oswald 1
- Ricardo Otheguy 1
- Inge Ott 1
- Ian Ottaway 1
- Robert Ottaway 2
- Susan Ottaway 2
- George Ottley 2
- Reginald Ottley 1
- Frederick Oughton 1
- Ouida 1
- Hermon Ould 1
- Ourselves 1
- Ian Ousby 1
- R.F. Outcault 2
- Ida Renthal Outhwaite 1
- Ruth Overman 1
- R.J. Overy 2
- Rasmus Ovesen 1
- J.D. Ovington 1
- Bryn Owen 1
- Charles Owen 1
- D.D.R. Owen 1
- David Owen 2
- David E. Owen 1
- Dorothy M. Owen 1
- Eleanor J. Owen 1
- Gareth Owen 2
- George Owen 2
- Geraint Dyfnallt Owen 1
- Griffith Owen 1
- Guillermo Owen 2
- Henry Owen 1
- Hugh Owen 2
- Hywel Wyn Owen 1
- Loris Owen 1
- Myrfyn Owen 1
- T.R. Owen 1
- Tony Owen 1
- Will Owen 1
- Victoria Owens 2
- Doug Owram 1
- Sibyl B. Owsley 5
- Helen Oxenbury 3
- Edward Oxenford 1
- Elsie J. Oxenham 116
- John Oxenham 2
- Eric Oxenstierna 1
- Chris Oxlade 2
- Alan Oxley 1
- Charles Oxley 2
- Mat Oxley 2
- Panama Oxridge 1