Other

The Common Horse. Once they were killed to keep other animals pure, but now they are one of the most common breed of horse in the UK. As they are a mix of breeds, there is a huge range in size, shape, colour and everything else you can think of, but they are usually loyal, trust worthy and hardy.

The breed you are referring to is called the Common Horse. There is no such thing as a mongrel horse..it is a term referring to a dog of mixed breeding.