The Vikings (1958) Kirk Douglas, Tony Curtis, Ernest Borgnine

Einar and Eric are two Viking halfbrothers. The former is a great warrior whilst the other is an exslave, but neither knows the true identity of the other. When the throne of Northumbria in Britain becomes free for the taking, the two brothers compete against one another for the prize, but they have very different motives both involving the princess Morgana, however.