1. A
  2. B
  3. C
  4. D
  5. E
  6. F
  7. G
  8. H
  9. I
  10. J
  11. K
  12. L
  13. M
  14. N
  15. O
  16. P
  17. Q
  18. R
  19. S
  20. T
  21. U
  22. V
  23. W
  24. X
  25. Y
  26. Z
  1. Terrie O'Brian
  2. Claire O'Brien
  3. Kiera O'Brien
  4. Kiera O'Brien
  5. Sean O'Brien
  6. Nicola O'Byrne
  7. Nicola O'Byrne
  8. Jonathan O'Callaghan
  9. David O'Connell
  10. Joanne O'Connell
  11. Des O'Connor
  12. Bridget O'Donnell
  13. Kim O'donnell
  14. Chris O'Dowd
  15. Sheila O'Flanagan
  16. Andrew O'Hagan
  17. Mo O'Hara
  18. Kate O'Hearn
  19. Owen O'Kane
  20. A. O'kif
  21. Amanda O'Neill
  22. Martin O'Neill
  23. Bill O'Reilly
  24. P J O'Rourke
  25. Ellie O'Ryan
  26. Ellie O'Shea
  27. Feargus O'Sullivan
  28. Kate O'Sullivan
  29. Kate O'Sullivan
  30. Ronnie O'Sullivan
  31. Suzanne O'Sullivan
  32. Peter O'Toole
  33. Nicky O’Byrne
  34. Katherine Tiernan O’Connor
  35. Dermot O’Leary
  36. Olusegun Obasanjo
  37. Obie Oberholzer
  38. Martine Oborne
  39. Jenny Offill
  40. Jenny Offill
  41. Sara Ogilvie
  42. Sara Ogilvie
  43. Ella Okstad
  44. Hans Olav Lahlum
  45. Jenny Oldfield
  46. Matt Oldfield
  47. Molly Oldfield
  48. Andrew Oldham
  49. Abi Oliver
  50. Mark Oliver
  51. Ramon Olivera
  52. Edith Olivier
  53. Sergio Olivotti
  54. Peter Olney
  55. Jacqueline Olson
  56. David Olusoga
  57. Michael Ondaatje
  58. Yoko Ono
  59. Hiawyn Oram
  60. János Orban
  61. Baroness Orczy
  62. Miguel Ordonez
  63. Jade Orlando
  64. David Orme
  65. David and Helen Orme
  66. Helen Orme
  67. Cheryl Orsini
  68. Julio Ortega
  69. Davide Ortu
  70. George Orwell
  71. Fiona Osbaldstone
  72. Jack Osbourne
  73. Kelsey Oseid
  74. Alice Oseman
  75. Richard Osmond
  76. Frank Ostaseski
  77. Matt Ottley
  78. Wil Overton
  79. Amanda Owen
  80. Sid Owen
  81. Lisa Owens
  82. Chris Oxlade
  83. Chris Oxlade
  84. Paul Oyer
  85. Helen Oyeyemi