The known history of the horse in Britain starts with horse remains found in Pakefield, Suffolk, dating from 700,000 BC, and in Boxgrove, West Sussex, dating from 500,000 BC. Early humans were active hunters of horses, and finds from the Ice Age have been recovered from many sites. At that time, land which now forms the British Isles was part of a peninsula attached to continental Europe by a low-lying area now known as "Doggerland," and land animals could migrate freely between what is now island Britain and continental Europe. The domestication of horses, and their use to pull vehicles, had begun in Britain by 2500 BC; by the time of the Roman conquest of Britain, British tribes could assemble armies which included thousands of chariots.
Horse improvement as a goal, and horse breeding as an enterprise, date to medieval times; King John imported a hundred Flemish stallions, Edward III imported fifty Spanish stallions, and various priories and abbeys owned stud farms. Laws were passed restricting and prohibiting horse exports and for the culling of horses considered undesirable in type. By the 17th century, specific horse breeds were being recorded as suitable for specific purposes, and new horse-drawn agricultural machinery was being designed. Fast coaches pulled by teams of horses with Thoroughbred blood could make use of improved roads, and coaching inn proprietors owned hundreds of horses to support the trade. Steam power took over the role of horses in agriculture from the mid-19th century, but horses continued to be used in warfare for almost another 100 years, as their speed and agility over rough terrain remained unequalled. Working horses had all but disappeared from Britain by the 1980s, and today horses in Britain are kept almost wholly for recreational purposes.