the welsh crosses well with many other breeds, and has influenced the [[pony of the americas]] and the british [[riding pony]]. many are also [[crossbreeding|cross-bred]] with [[thoroughbred]]s, and other [[list of horse breeds|horse breeds]]. the welsh pony has contributed to the founding of several other horse and pony breeds. the [[morgan horse]] is one such breed, being in part descended from welsh cobs left behind by british forces after the end of the [[american revolutionary war]]. they are crossed with arab horses to produce riding horses, and with [[thoroughbred]]s to produce [[show jumping|jumpers]], hunters, and [[eventing|eventers]]. welsh mares have also been used to breed [[polo|polo ponies]] that were agile and nimble. the welsh pony was used to create the [[welara]], a cross-breed of the welsh and the arab horse, which has been registered in america as a separate breed since 1981.