| William Kenyon-Slaney | William Keppel | William Keppel, IV conte di Albemarle |
| William Keppel, VII conte di Albemarle | William Ker | William Kermack |
| William Kerr | William Kerr (Royal Navy) | William Kerr, II marchese di Lothian |
| William Kerr, III marchese di Lothian | William Kerr, IV marchese di Lothian | William Kerr, V marchese di Lothian |
| William Kerr, VI marchese di Lothian | William Keys | William Kidd |
| William Kiernan | William Kilgour Jackson | William King |
| William King (geologo) | William King Gregory | William Kingdon Clifford |
| William Kinnear | William Kiptum | William Kirby |
| William Kirby Cullen | William Kircher | William Kirschbaum |
| William Kirshbaum | William Kissam Vanderbilt | William Klein |
| William Klinger | William Kneale | William Knight |
| William Knight (pirata) | William Knowles | William Knox Martin |
| William Komenich | William Konchellah | William Kooistra |
| William Kotsores | William Kotzwinkle | William Kristol |
| William Kruppinger | William Kruskal | William Kunstler |
| William Kurelek | William Kurt Black | William Kurtović |
| William Kurtovic | William Kuster | William Kvist |
| William Kvist Jørgensen | William Kwabena Tiero | William Kwong Yu Yeung |
| William Kyle Carpenter | William L. Anderson | William L. Ball |
| William L. DeAndrea | William L. Deandrea | William L. Dodge |
| William L. Hendricks | William L. Langer | William L. Marcy |
| William L. Petersen | William L. Shirer | William Labov |
| William Lacey | William Lacy Clay | William Lacy Clay, Jr. |
| William Ladd | William Lafayette Strong | William Lai |
| William Lakin Turner | William Lamb | William Lamb Picknell |
| William Lamb, II visconte Melbourne | William Lamberton | William Lamont Strothers |
| William Lampe | William Lamport | William Lance Berkman |
| William Lance LeGault | William Landay | William Lane |
| William Lane Craig | William Lange | William Langer |
| William Langewiesche | William Langland | William Lanteau |
| William Laparra | William Larned | William Larry Stewart |
| William Lashly | William Lassell | William Latimer |
| William Laud | William Laurence Bingham | William Laurence Burns |
| William Laurence Cumpanas | William Laurie | William Lava |
| William Lawes | William Lawrence Boyd | William Lawrence Bragg |
| William Lawrence Chittenden | William Lawrence Hicke | William Lawrence McDonald |
| William Lawrence Sebok | William Lawrence Shirer | William Lawvere |
| William Layton Roaf | William Le Baron Jenney | William Le Pogam |
| William le Scrope | William le Scrope, I conte di Wiltshire | William Leahy |
| William Lear | William Learned Marcy | William Least Heat- Moon |
| William Least Heat-Moon | William LeBaron | William LeBaron Jenney |
| William Lebghil | William Lechner | William Lee |
| William Lee Conley Broonzy | William Lee Scott | William Lee Shoemaker |
| William Lee Wilder | William Legge | William Legge, I conte di Dartmouth |
| William Legge, II conte di Dartmouth | William Legge, IV conte di Dartmouth | William Legge, V conte di Dartmouth |
| William Legge, VI conte di Dartmouth | William Legge, X conte di Dartmouth | William Lehman |
| William Lehman (politico) | William Leighton | William Leishman |
| William Lendrum Mitchell | William Lenoir | William Lenthall |
| William Leon Barmore | William Leon Behr | William Leon Garrett |
| William Leonard Langer | William Leonard Rowe | William Lescaze |
| William Leslie | William Leslie (attore) | William Leslie Johnson |
| William Lester | William Lester Suff | William Leushner |
| William Levada | William Leveson-Gower | William Leveson-Gower, IV conte di Granville |
| William Levy | William Lewin | William Lewis |
| William Lewis (arbitro) | William Lewis (atleta) | William Lewis (scacchista) |
| William Lewis Elkin | William Lewis Manly | William Lewis Moore |
| William Lewis Owens | William Lewis Shaw | William Light |
| William Liller | William Lilly | William Lincoln |
| William Lincoln Bakewell | William Lincoln Christie | William Lindsay |
| William Lindsay (calciatore 1872) | William Lindsay Gresham | William Lindsay White |
| William Ling | William Linich | William Link |
| William Lipinski | William Lipscomb | William Lipz |
| William Lister | William Livingston | William Lloyd |
| William Lloyd (attore) | William Lloyd Garrison | William Lloyd Warner |
| William Lloyd Webber | William Lobb | William Lockhart Clayton |
| William Lockwood | William Lombardy | William Longstreth Dodge |
| William Lopez (Marvel Cinematic Universe) | William Loud Bendigo International | William Loud Bendigo International 2 2013 |
| William Loud Bendigo International 2 2013 - Doppio | William Loud Bendigo International 2 2013 - Singolare | William Loud Bendigo International 2011 |
| William Loud Bendigo International 2011 - Doppio femminile | William Loud Bendigo International 2011 - Singolare femminile | William Loud Bendigo International 2012 |
| William Loud Bendigo International 2012 - Doppio femminile | William Loud Bendigo International 2012 - Singolare femminile | William Loud Bendigo International 2013 |
| William Loud Bendigo International 2013 - Doppio | William Loud Bendigo International 2013 - Singolare | William Louis DeAndrea |
| William Louis Petersen | William Louis Reteneller | William Louis Sharp |
| William Louis Stricker | William Louis Wallace | William Lovett |
| William Lowther, II baronetto | William Lubtchansky | William Luckey |
| William Lucking | William Ludwig | William Lundigan |
| William Lundin | William Lustig | William Luther Hill |
| William Lutley Sclater | William Lygon | William Lygon Pakenham |
| William Lygon, VII conte Beauchamp | William Lyman | William Lynch |
| William Lyne | William Lyne Wilson | William Lyon |
| William Lyon Mackenzie | William Lyon Mackenzie King | William Lyons |
| William Lyttelton | William Lyttelton, III barone Lyttelton | William M. Anderson |
| William M. Branham | William M. Burton | William M. Daley |
| William M. Evarts | William M. Fechteler | William M. Gray |
| William M. Hoffman | William M. Jennings Trophy | William M. Mann |
| William M. Marston | William M. Meredith | William M. Nicholson |
| William M. Ramsay | William M. Tuck | William M. Tweed |
| William M. Wheeler | William Mac Guckin de Slane | William MacAskill |
| William MacCormac | William MacCormick | William MacDougal |
| William MacFadyen | William MacGillivray | William Machado de Oliveira |
| William Mackay | William MacKenzie | William Mackenzie |
| William MacKinnon | William Maclay | William MacMillan |
| William Macy | William Maddock Bayliss | William Magarity |
| William Magear Tweed | William Maher | William Mahony |
| William Mahony O'Brien | William Makepeace Thackeray | William Malcolm Dickey |
| William Maldonado | William Malet | William Malone |
| William Mang | William Mangion | William Mansfield Clark |
| William Manson | William Mapother | William Maragh |
| William Marçais | William Marbury | William Marcais |
| William March | William March (sollevatore) | William Marcus Henderson Rose |
| William Marcus Paul Stewart | William Marcy | William Marion Hougland |
