Vikings sailing from Scandinavia to England brought horses, dogs and possibly even pigs with them, according to analysis of bone remains.
It was previously thought that the Vikings stole most of the animal invasion from British villages.
The findings also provide evidence that Viking leaders had close relationships with animals and traveled with them, says the leading scientist.
9th Century bones found in burial mounds in Heath Wood, Derbys.
Animal and human cremated remains were found mixed together, suggesting that the creatures had special meaning and were burned on the same funeral pyre as humans, said doctoral researcher Tessi Löffelmann, from Durham University and Vrije Universiteit in Brussels , by BBC News.
“They were treated more like companion animals rather than just for economic purposes,” she said.
“It makes me very happy and suggests that we underestimate how important animals were to the Vikings.”
The horses and dogs would travel in Viking longboats across the North Sea, a journey that could take several weeks.
“Horses back then were smaller than horses are now, which might have made the ride a bit nicer, but it was probably still wet and uncomfortable,” said Miss Löffelmann.
Professor Julian Richards, from the University of York, who co-directed the excavations, said: “The Bayeux Tapestry shows Norman cavalry arriving from their fleet on horseback but this is the first scientific evidence that Viking warriors were transporting horses to England 200 years earlier. “
Norse mythology and 13th Century sagas show that animals played a major role in the life of the Vikings.
The scientists also found a pig bone in Heath Wood, the only large Viking cremation site in Britain, but this may have been a token or part of a game brought from Scandinavia, rather than a live animal.
They discovered that the animals came from Scandinavia by analyzing the strontium in their bones.
This element occurs naturally in rocks, soil and water, before making its way into plants – and, when they eat these, bones and teeth.
Archaeologist Cat Jarman, who worked at Heath Wood but was not involved in the research, said the use of this technique on cremated bone was “very exciting” as many Scandinavian burials used cremation.
“It opened up a whole new avenue of evidence,” she said.
The results are published in the scientific journal Plos One.