Authors
- Kyle Olmon
- Frederick Law Olmsted
- John Olmsted
- John M.H. Olmsted
- Merle Olmsted
- Merle C. Olmsted
- Robert P. Olmsted
- Don Olney 1
- James Olney
- P.J.S. Olney
- Peter Olney
- Peter J.S. Olney
- Richard Olney
- Nicholas Olsberg
- P.J. Olscamp
- Alfred Olschewski
- Bjorn Olsen
- Carl Olsen
- Catherine Olsen
- Donald J. Olsen
- Frederick L. Olsen
- Jack Olsen
- Jerry Olsen
- John Andreas Olsen 1
- Klaus Malling Olsen 2
- Lars-Henrik Olsen 1
- Oluf Reed Olsen
- Penny Olsen
- Robert Olsen
- Tom Olsen
- Kathe Olshausen-Schonberger
- C. Olson
- Donald S. Olson
- Douglas D. Olson
- Elder Olson
- Gary D. Olson 1
- Harry F. Olson
- James S. Olson 1
- Lester C. Olson
- Lynne Olson
- Olle Olson
- Randall Olson
- Robert E. Olson
- Roberta Olson
- Roberta J.M. Olson 1
- Storrs L. Olson 1
- Henrik Olsson 1
- Urban Olsson
- Albert B. Olston
- Lucia Olteanu
- James H. Olthuis
- Thomas F. Oltmanns
- Frank Calvert Oltorf
- Gabriel Olusanya
- David Olusoga
- David Oluwale
- Nils-Goran Olve
- Elwood F. Olver
- George Olver
- Ron Olver
- Stephen Olvey
- E.M. Olville
- Frank Olynyk 1
- Piet Olyslager
- Oman
- C.W.C. Oman
- Carola Oman
- Charles Oman
- Julia Trevelyan Oman
- Sir Charles Oman
- Donald Omand
- Wilfrid Omer-Cooper
- F.D. Ommanney
- George W.T. Omond
- Kennedy Onasis
- Aristotle Onassis
- Jacqueline Onassis
- Georges Onclincx
- Christopher Ondaatje
- Michael Ondaatje
- Hans Onderwater
- S. Ondrej
- Oneida Community
- Richard Oney
- Michel Onfray
- John Onians
- Rosalind Onians
- Oniell
- C.T. Onions
- Oliver Onions
- Katsuhito Onishi
- Graham Onley
- Chin Kee Onn
- Yoko Ono
- C.F.A. Onochie
- Hiroo Onoda
- Urgunge Onon
- Dorothy Onslow
- John Onslow
- Phipps Onslow