The three Viking ships in the film were designed using blueprints for an actual Viking ship salvaged from the water and restored by a Viking museum in Norway. It turned out that the boats built for the film were too accurate, because the modern actors were taller than their historical counterparts. Every second oar hole had to be plugged so the modern men would have room to row with a full oar stroke. Otherwise, they would hit the backs of the oarsmen seated in front of them when pushing the oar handles forward to start each new stroke.

Ernest Borgnine plays Ragnar, the father of Einar (Kirk Douglas). In real life Borgnine is only one and a half months younger than Douglas.

More than 4,000 performers, technicians and artisans from 16 different countries worked on the film, forcing the director's instructions to be translated into seven languages.

At the end of the film, a Viking ship is set afire by flaming arrows in a rendering of a traditional Viking funeral. Director Richard Fleischer took great care to have the archers practice the moment, training them to release the arrows on the count of "three," and hoping at least some of the arrows would arc properly to hit the sail of the ship and set it on fire. When the time came for the live shot, the director only reached the count of "two", when an over-eager archer loosed his arrow. As luck would have it, the arrow arced perfectly and hit the sail. Then, Fleischer called, "Three." and the other archers loosed their arrows. Fleischer decided that he liked the one, single arrow being launched first, and kept the shot in the film because it looked like part of the ceremony.