| Travis Fimmel | Ragnar Lothbrok |
| Clive Standen | Rollo |
| Katheryn Winnick | Lagertha |
| Jessalyn Gilsig | Siggy Haraldson |
| Gabriel Byrne | Earl Haraldson |
| Gustaf Skarsgård | Floki |
| George Blagden | Athelstan |
| John Kavanagh | The Seer |
| Ivan Kaye | King Aelle |
| David Pearse | Svein |
| Nathan O'Toole | Bjorn Lothbrok |
| Gavan O'Connor-Duffy | Housecarl 1
(as Gavan Duffy) |
| Trevor Cooper | Earl Bjarni |
| Elinor Crawley | Thryi |
| Ruby O'Leary | Gyda |
| Jefferson Hall | Torstein |
| Diarmaid Murtagh | Leif |
| Tadhg Murphy | Arne |
| Maude Hirst | Helga |
| Angus MacInnes | Tostig |
| Roanna Cochrane | Slave Girl |
| Alexis Forbes | Old Woman /
Grim Giantess
(as Christina Forbes) |
| Dez McMahon | Haraldson Kinsman |
| Michael Liebmann | Saxon Messenger |
| Jonathan Kemp | Wigea
(as Jonathon Kemp) |
| Peter Gaynor | Lord Edgar |
| Lexi Rose | Angel of death /
Old woman |
| Robert MacDomhnail | Viking Warrior
(uncredited) |