Clive Owen
Arthur
Ioan Gruffudd
Lancelot
Keira Knightley
Guinevere
Mads Mikkelsen
Tristan
Joel Edgerton
Gawain
Hugh Dancy
Galahad
Ray Winstone
Bors
Stephen Dillane
Merlin
Ray Stevenson
Dagonet
Til Schweiger
Cynric
Stellan Skarsgård
Cerdic
Sean Gilder
Jols
Ken Stott
Marius Honorius
Charlie Creed-Miles
Ganis
David Murray
Merlin's Lieutenant
Ned Dennehy
Mental Monk
Phelim Drew
Obnoxius Monk
Des Braiden
Third Monk
Bosco Hogan
Bishop Decoy
David Wilmot
Woad Killed by Lancelot
Lochlann O'Mearáin
Roman Commander
Ivano Marescotti
Bishop Germanus
Clive Russell
Lancelot's Father
Graham McTavish
Roman Officer
Dessie Gallagher
Mercenary
Elliot Henderson-Boyle
Young Lancelot
Owen Teale
Pelagius (uncredited)
Dawn Bradfield
Vanora
Pat Kinevane
Horton