| Name | Character | Episodes |
|---|---|---|
| John Colicos | Patrick Henry | 2 |
| Carl Benton Reid | Calhoun | 2 |
| Walter Matthau | Gov. John Slaton | 1 |
| Walter Matthau | Andrew Johnson | 1 |
| James T. Callahan | Barnes | 1 |
| George Rose | Sen. Thomas Corwin | 1 |
| Harry Bellaver | Hale | 1 |
| Burgess Meredith | John Peter Altgeld | 1 |
| David McCallum | John Adams | 1 |
| Tom Bosley | Senator George W. Norris | 1 |
| Victor Jory | Charles Carlin | 1 |
| Dan O'Herlihy | Professor Richard T. Ely | 1 |
| Geraldine McEwan | Jesse | 1 |
| Carroll O'Connor | Grover Cleveland | 1 |
| Brian Keith | Thomas Hart Benton | 1 |
| Karl Swenson | Chynoweth | 1 |
| Laurence Naismith | John Adams | 1 |
| Laurence Naismith | George Mason | 1 |
| Tim O'Connor | Rigdon | 1 |
| Slim Pickens | Rogers | 1 |
| Paul Fix | William Brownlow | 1 |
| Warren Stevens | Lt. Gov. Edward Clark | 1 |
| John Crawford | 1 | |
| Barbara Feldon | Frances Cleveland | 1 |
| Rosemary Harris | Mary S. McDowell | 1 |
| John Abbott | Senator Wigfall | 1 |
| Bradford Dillman | Edmund G. Ross | 1 |
| Marsha Hunt | Mrs. Ely | 1 |
| John Hoyt | Mr. Finchley | 1 |
| John Hoyt | Lodge | 1 |
| Strother Martin | Senator James Wadsworth | 1 |
| Ford Rainey | Bird | 1 |
| Barry Morse | Thaddeus Stevens | 1 |
| Paul Stewart | Louis D. Brandeis | 1 |
| Peter Lawford | Gen. Alexander Doniphan | 1 |
| H.M. Wynant | 1 | |
| George Macready | General Fairchild | 1 |
| Neil Hamilton | Gov. John Winthrop | 1 |
| Conlan Carter | Robert Johnson | 1 |
| Peter Whitney | Gronna | 1 |
| David Brian | Charlton | 1 |
| Christopher Dark | Hay | 1 |
| John Howard | Sen. Crittenden | 1 |
| Donald Harron | John Cotton | 1 |
| Donald Harron | Governor Randolph | 1 |
| Torin Thatcher | Sewall | 1 |
| Torin Thatcher | Cannon | 1 |
| Sue Randall | Joan Owens | 1 |
| Wesley Addy | Hellinger | 1 |
| Lamont Johnson | Fremont | 1 |
| Edith Atwater | Mrs. Andrews | 1 |
| John Cassavetes | Parsons | 1 |
| Leonard Nimoy | Burr Jones | 1 |
| J.D. Cannon | Sam Houston | 1 |
| Ed Asner | Oliver E. Wells | 1 |
| Ed Asner | President Ulysses S. Grant | 1 |
| Andrew Prine | Josiah Quincy | 1 |
| Henry Jones | Hamilton Fish | 1 |
| Woodrow Parfrey | Governor William Brandon | 1 |
| Woodrow Parfrey | Principal Ralston | 1 |
| Gary Merrill | John Marshall | 1 |
| Albert Salmi | Mr. Schneider | 1 |
| Simon Oakland | Captain Bogart | 1 |
| Simon Oakland | Perry Fuller | 1 |
| Whit Bissell | Myles | 1 |
| Whit Bissell | Woodrow Wilson | 1 |
| George Lindsey | Black | 1 |
| Meg Wyllie | Eliza | 1 |
| Alfred Ryder | Garrison | 1 |
| Alfred Ryder | Senator Nicholson | 1 |
| Roy Barcroft | Judge | 1 |
| Parley Baer | Hillhouse | 1 |
| Michael Pate | John Wilson | 1 |
| Milton Selzer | Schilling | 1 |
| Arthur Franz | James Madison | 1 |
| Michael Constantine | Watson | 1 |
| Wendy Hiller | Anne Hutchinson | 1 |
| Howard St. John | Hinrichsen | 1 |
| Lee Tracy | Senator Robert A. Taft | 1 |
| Joseph Ruskin | French | 1 |
| King Donovan | Rev. Mr. May | 1 |
| Alan Baxter | Traine | 1 |
| George Grizzard | Judge Ben Barr Lindsey | 1 |
| George Furth | Stanley | 1 |
| George Mitchell | Mr. Broomell | 1 |
| Peggy McCay | Margaret | 1 |
| John Kerr | Whitlock | 1 |
| Harry Townes | Coffin | 1 |
| Kevin Hagen | Sweet | 1 |
| David Opatoshu | Max Goldman | 1 |
| Rhys Williams | William Hutchinson | 1 |
| Peter Mark Richman | Rawlins | 1 |
| Philip Ober | Anderson | 1 |
| Sidney Blackmer | Oscar W. Underwood | 1 |
| Martine Bartlett | Caroline | 1 |
| Peter Hobbs | Lindbergh | 1 |
| James Westerfield | Sen. Samuel Pomeroy | 1 |
| Booth Colman | Aaron Burr | 1 |
| Herschel Bernardi | Gen. Daniel Sickles | 1 |
| Herb Voland | La Follette | 1 |
| Herb Voland | Peckham | 1 |
| Russell Collins | Foote | 1 |
| Russell Collins | Adams Sr. | 1 |
| Paul Lambert | Whitney | 1 |
| Betsy Jones-Moreland | Sally | 1 |
| Sandy Kenyon | Webster | 1 |
| Phyllis Love | Abigail Adams | 1 |
| Jason Wingreen | Hanson | 1 |
| Paul Comi | Samuel Quincy | 1 |
| Tol Avery | William Jennings Bryan | 1 |
| William Bakewell | Wythe | 1 |
| Robert Hooks | Frederick Douglass | 1 |
| Loring Smith | Roger Marsden | 1 |
| Janice Rule | Prudence Crandall | 1 |
| Frances Sternhagen | Miss Koeller | 1 |
| Dan Tobin | 1 | |
| Kent Smith | Charles Evans Hughes | 1 |