so he couldn't have his caique and Edith too

There is yet another version, which I am certain is apocryphal, that Eric was carrrying a Papal Bull (or edict) back to Scandinavia and was attacked by pagan pirates who confiscated the ship so that the Bull should not be delivered. Maybe you heard the same version, Geoff, but delivered by a Castillian.

This may also be the origin of Bullship