Authors
- Donald R. Ostberg
- C.H. Ostenfeld
- Martha Ostenso
- Maggie Oster
- Geoffrey Ostergaard
- Troels V. Ostergaard
- J. Osterhammel
- Gunter Osterloh
- Jonny Osterman 1
- Doris B. Osterwald
- E. Ostick
- Dennis Ostle
- George Ostler
- Nicholas Ostler
- Mike Ostlund
- F. Darl Ostrander
- Fannie E. Ostrander
- S. Ostrander
- Simi I. Ostric
- Yvonne Ostroga 1
- George Ostrogorsky
- Charles W. Ostrom 1
- Ivan Ostroukhov
- Victor Ostrovsky
- Wanda Ostrowska
- Adrian Oswald
- Alice Oswald
- Andrena Oswald
- Arthur Oswald
- Felix Oswald
- James Oswald
- Lee Harvey Oswald
- P.H. Oswald
- Werner Oswald 1
- Oswald The Second
- Julie Oswin
- Jeanna Oterdahl
- Andrei Otetea
- Ricardo Otheguy 1
- A.N. Other
- James Otis
- L.L. Otis
- David Otley
- Bertrand Ott
- Arvid Ottar
- Ian Ottaway 1
- John Ottaway
- Mark Ottaway
- Patrick Ottaway
- Reginald H. Ottaway
- Robert Ottaway 2
- Susan Ottaway 1
- Alfred Otte
- Daniel Otte
- Otted
- D. Otten
- Terry Otten
- Laurence Ottenheimer
- Huib Ottens
- Otter
- Ken Otter
- Patrick Otter
- David Ottewell
- David J. Ottewell
- Gordon Ottewell
- John Ottewell
- Roy Ottey
- Bill Ottinger
- J.M. Ottino
- George Ottley 2
- R.L. Ottley
- Reginald Ottley 1
- Roi Ottley
- Frederick W. Otto
- Jacob Augustus Otto
- Svend Otto S.
- Lars-Henrik Ottoson
- Graham Otway
- Helen Otway
- Thomas Otway
- Annette J. Otway-Ruthven
- Marc-Alain Ouaknin
- A.C. Oudermans
- Piet Oudolf
- William Ouellette
- C. Oughton
- Frederick Oughton 1
- J.D. Oughton
- James D. Oughton
- Iain Oughtred
- Ouida 1
- Hermon Ould 1
- Ouless
- Tore Ouren
- Edouard Ourliac
- Raymond Oursel
- Ourselves 1
- Bill Oursler
- Fulton Oursler
- John H. Ousbey