#4 Pest control required a dog that could hunt effectively, and in a pack.

A small hunting dog was needed for fighting in burrows, brave, hardy, with a high speed of running, in order to keep up with hounds and hunters on horseback. It should interact well with other game animals as well as other farm animals.
#5 It was this breed that farmers managed to bring out in the 17th century.

#6 Unsurprisingly, it is still popular in Britain and appreciated in the rest of the world.
