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  1. O'Brien, Lucy
  2. O'Brien, Sean
  3. O'Byrne, Nicola
  4. O'Byrne, Nicola
  5. O'Connell, Joanne
  6. O'Connor, Bridget
  7. O'Connor, Deborah
  8. O'Connor, Elizabeth
  9. O'Donnell, Bridget
  10. O'Dowd, Chris
  11. O'Hara, Lauren
  12. O'Hara, Mo
  13. O'Hara, Natalia
  14. O'Hare, Gráinne
  15. O'Kane, Owen
  16. O'Neill, A.D.
  17. O'Neill, Amanda
  18. O'Neill, Heather Aimee
  19. O'Neill, Martin
  20. O'Reilly, Bill
  21. O'Rourke, P. J.
  22. O'Sullivan, Ronnie
  23. Oakley, Stu
  24. Oates, Joyce Carol
  25. Obasanjo, Olusegun
  26. Oborne, Martine
  27. Odette, Tessonja
  28. Odo
  29. Ogilvie, Sara
  30. Ojari, Daniel
  31. Olav Lahlum, Hans
  32. Oldfield, Matt & Tom
  33. Oliver, Abi
  34. Oliver, Joshua
  35. Olivotti, Sergio
  36. Ollerton, Ollie
  37. Olley, Darcie
  38. Olson, Jessica S.
  39. Olson, Parmy
  40. Olusoga, David
  41. Olusoga, Kemi
  42. Olusoga, Yinka
  43. Ondaatje, Michael
  44. Ono, Yoko
  45. Orczy, Baroness
  46. Ord, Charlotte
  47. Orie, Rima
  48. Orlando, Jade
  49. Ortega, Julio
  50. Orwell, George
  51. Oseid, Kelsey
  52. Osmond, Richard
  53. Ostaseski, Frank
  54. Otis, Andrew
  55. Ounsley, Jodie
  56. Owen, Amanda
  57. Owen, Sid
  58. Owens, Lisa
  59. Oxenbury, Helen
  60. Oxlade, Chris
  61. Oyemakinde, Tomi
  62. Oyeyemi, Helen
  63. Ozawa, Eric
  64. O’Connor, Katherine Tiernan
  65. O’Hart, Sinéad
  66. O’Neill, Eamonn