Researchers from Durham University and the Free University of Brussels have found what they say is the first evidence that the Vikings came to Britain with their dogs and horses, PLOS ONE reported.

Archaeologists studied animal and human remains found in the Heath Wood funeral pyre, which belonged to ancient Vikings who invaded Britain in the ninth century. Strontium isotope analysis showed that one adult man, a horse, a dog and a pig sailed together from Scandinavia and died shortly after arriving in Britain.

The results mean that the Vikings not only stole animals upon arrival in Britain, as the sources of the time describe, but also transported them from Scandinavia. In addition, the Vikings apparently valued their animals enough to take them on trips. When a warrior died the animal was buried with him in the funeral pyre. The remains of the pig were probably an offering to the gods.

Strontium is found in the environment in rocks, soil and water, from where it enters plants. When humans and animals eat these plants, strontium replaces calcium in their bones and teeth. Because the ratio of strontium varies in different parts of the world, it is possible to determine where they lived by the ratio of isotopes.

The authors noted that the Bayeux tapestry depicts Norman cavalry unloading horses from a ship before the battle of Hastings. But their study was the first scientific demonstration that Viking warriors transported horses two hundred years before that battle.