| Athenagoras I | Greek Clergyman |
| Baudouin I | Belgian Royalty |
| Elizabeth I | English Royalty |
| Ferdinand I | German Royalty |
| Justinian I | Roman Statesman |
| Isabella I | Spanish Royalty |
| Stanislaus I | Polish Royalty |
| Lee Iacocca | American Businessman |
| Janis Ian | American Musician |
| Scott Ian | American Musician |
| Dolores Ibarruri | Spanish Politician |
| Jacques Ibert | French Composer |
| Ali ibn Abi Talib | |
| Solomon Ibn Gabirol | Spanish Poet |
| Abdullah Ibrahim | |
| Henrik Ibsen | Norwegian Poet |
| Masaru Ibuka | Japanese Businessman |
| Carl Icahn | American Businessman |
| Vanilla Ice | American Musician |
| David Icke | English Athlete |
| Harold L. Ickes | American Politician |
| Jacky Ickx | Belgian Celebrity |
| Eric Idle | English Comedian |
| Billy Idol | British Musician |
| Gwen Ifill | American Journalist |
| Robert Iger | American Businessman |
| Enrique Iglesias | Spanish Musician |
| Julio Iglesias | American Musician |
| Michael Ignatieff | Canadian Politician |
| Saint Ignatius | Spanish Saint |
| James Iha | American Musician |
| Abdallah II | |
| Catherine II | Russian Statesman |
| Charles II | |
| Edward II | English Royalty |
| Elizabeth II | British Royalty |
| Frederick II | |
| Margrethe II | Danish Royalty |
| Nicholas II | Russian Royalty |
| George III | English Royalty |
| Daisaku Ikeda | Japanese Writer |
| Kim Il Sung | |
| Robert Iler | American Actor |
| Ivan Illich | American Sociologist |
| Josefa Iloilo | Fijian Statesman |
| Natalie Imbruglia | Australian Musician |
| Michael Imperioli | American Actor |
| Don Imus | American Celebrity |
| Luiz Inacio Lula da Silva | Brazilian Politician |
| Hazrat Inayat Khan | |
| Paul Ince | English Athlete |
| Robert Indiana | American Artist |
| Miguel Indurain | Spanish Athlete |
| Guillermo C. Infante | |
| Laura Ingalls Wilder | American Author |
| Dean Inge | English Author |
| Jean Ingelow | English Poet |
| Bernard Ingham | British Journalist |
| Bob Inglis | American Politician |
| Charles Inglis | Canadian Clergyman |
| Laura Ingraham | American Celebrity |
| Helge Ingstad | Norwegian Explorer |
| James Inhofe | American Politician |
| Laura Innes | American Actress |
| Neil Innes | British Writer |
| Daniel Inouye | American Politician |
| Jay Inslee | American Politician |
| Tony Iommi | English Musician |
| Eugene Ionesco | French Dramatist |
| Muhammad Iqbal | Pakistani Poet |
| Muhammed Iqbal | Indian Poet |
| Jill Ireland | English Actress |
| Kathy Ireland | American Model |
| Patricia Ireland | American Activist |
| Donnie Iris | American Musician |
| Jack Irons | American Musician |
| Jeremy Irons | English Actor |
| Michael Ironside | Canadian Actor |
| Michael Irvin | American Athlete |
| Eddie Irvine | Irish Celebrity |
| Chester Irving Barnard | American Businessman |
| Amy Irving | American Actress |
| Clifford Irving | American Writer |
| David Irving | British Author |
| Edward Irving | Scottish Clergyman |
| Henry Irving | English Actor |
| John Irving | American Novelist |
| Julius Irving | American Athlete |
| Washington Irving | American Writer |
| William Irwin Thompson | American Philosopher |
| Bill Irwin | American Entertainer |
| James Irwin | American Astronaut |
| Steve Irwin | Australian Scientist |
| Jerome Isaac Friedman | American Physicist |
| Theodore Isaac Rubin | American Psychologist |
| Jason Isaacs | English Actor |
| Chris Isaak | American Musician |
| Johnny Isakson | American Politician |
| Christopher Isherwood | American Author |
| Kazuo Ishiguro | Japanese Author |
| Shintaro Ishihara | Japanese Politician |
| Michael Isikoff | American Journalist |
| Isocrates | Greek Writer |
| Steve Israel | American Politician |
| Alec Issigonis | Turkish Designer |
| Ernest Istook | American Politician |
| Silius Italicus | |
| Joichi Ito | Japanese Businessman |
| Lance Ito | American Judge |
| Henry IV | |
| Goran Ivanisevic | Croatian Athlete |
| Igor Ivanov | Russian Statesman |
| George Ivanovitch Gurdjieff | Russian Educator |
| Allen Iverson | American Athlete |
| Burl Ives | American Musician |
| Charles Ives | American Composer |
| David Ives | American Playwright |
| Molly Ivins | American Journalist |
| Keenen Ivory Wayans | American Comedian |
| Alija Izetbegovic | Bosniak Activist |
| Eddie Izzard | British Comedian |