While cats are a much-loved house pet today, in Viking times, it took a little while for the Norse to warm to the local felines. Literally, warming is exactly what the cats were doing to the Vikings as their pelts were often used for clothing, a new study has found. However, over time, cats managed to worm their way into the affection of the Norse and even managed to journey far and wide with them as the Vikings went exploring.

A new study, as reported on by Science, reveals that many Viking Age cats were initially collected to make pelts which were used in clothing. In fact, the Danish were collecting a high price for their cat pelts by 850–1050 C.E.

Julie Bitz-Thorsen, an undergraduate at the University of Copenhagen, and her adviser, archaeozoologist Anne Birgitte Gotfredsen, recently examined a multitude of bones stored at the Zoological Museum in Copenhagen. These bones had been collected from various locations across Denmark and covered a timeframe of more than 2,000 years, starting in the Bronze Age and ending in the 1600s.

Surprisingly, many cat bones were found. Previously, cats bones had usually been less prevalent in archaeological digs pertaining to domesticated animals, so the find was quite significant.

“I do not know of any other series of cat bones that cover such a long period, with so many individuals,” archaeozoologist Wim Van Neer of the Royal Belgian Institute of Natural Sciences in Brussels said.

The new study then delved into the domestication of the animals — as well as the nefarious use Vikings originally had for the creatures.

“You can tell the cats were skinned — they have cut marks, or the neck has been broken,” Bitz-Thorsen revealed.

It has also been discovered that the Vikings eventually moved on from merely using cats for their pelts to start keeping the felines as domesticated animals used for rodent control. In fact, some cats traveled across the Mediterranean with the Vikings as they explored and raided. It is believed these cats were kept on board to help keep down rodent numbers which could decimate supplies during long sea journeys.

In addition, new research, published this month in the Danish Journal of Archaeology, has found that cats are fairly unique with their domestication. While animals usually shrink in size upon domestication, cats have actually increased in size by as much as 16 percent since they became domesticated.

“Such a shift has never been documented elsewhere, as far as I know,” says Van Neer, who was not involved in the study.

While there is a theory that cats increased in size with domestication, further research will have to be done in order to determine whether this theory is correct or not.