Why were ferrets domesticated?

The history of the ferret's domestication is uncertain, like that of most other domestic animals, but it is likely that ferrets have been domesticated for at least 2,500 years.They are still used for hunting rabbits in some parts of the world today, but increasingly they are being kept simply as pets.

It is known that the Roman's used ferrets for hunting rabbits. When the Roman Army was invading Europe they introduced rabbits for food purposes and brought along the ferrets for rabbit hunting