Arabian Horses were imporoved in speed and endurance over time through breeding.
Although it is easy for a Transportation Historian to focus on developments that improved or effected the modern, industrial, and post-industrial world; I don't want to give the impression that the age of the horse was completely lacking in the spirit of innovation or improvement. Horses were consistently improved over time, by the process of selective breeding. The most famous example of this is probably the Arabian horse.
The origins of the Arabian are lost in time, although most Muslims give the credit for founding the breed to Ishmael, son of Abraham, others trace it back to Noah. The Koran praises good horses. The fact is that a large part of the early History of the Middle East is marked by a long series of invasions and conquests by horse riding nomadic peoples. The wealth of the great agricultural cities of Mesopotamia consistently drew warlike nomads down off the Asian steppes. The conquerors then usually tended to set themselves up to rule the city, but usually became assimilated into the existing culture. Then, after some time, another wave of fierce nomads would roll down off the steppes. The Huns, the Mongols, and the Turks are probably the best known examples of this phenomenon, although it is much older than any of those.
So, it should not be surprising that the Arabian, in many ways the best light horse in the world, should be found there. Arabians are famous for their endurance, stamina, and speed. Virtually every thoroughbred alive today has at least some Arabian blood. Selective breeding over the thousands of years that horses were a key technology for both transportation and war made the Arabian what it was, and is.
When Islam came to dominate the region they prized the best horses, and kept track of their breeding through the mare's line. The best mares were worth a king's ransom, and in the Arabian desert, where there was little grass, horses were fed almost as well as men; on dates, camel milk, and barley. Bedouins had a tradition of racing their horses with the winner taking the best horses from the losers herd, thus consolidating the best stock. By being so well taken care of, and so highly prized, the best horses demanded the best prices and the rich and powerful acquired the best of the best to breed with their existing stock. So it was that the Arabian became perhaps the best horse in the world in many ways.
At points when Europeans came into contact with Islam, such as Spain, Southern France, and Eastern Europe, and also during the crusades. Heavier European horses were bred with Arabians to improve their stamina and speed. The Percheron is one such example. Arabians abandoned by Moors after their defeat in southern France added Arabian blood to French stock in the 8th Century. Crusaders brought back Arabians, the Hapsburgs in Austria sought them out, Frederick the Great of Prussia imported them to improve his cavalry stock. By the present time, at least some Arabian blood is probably in almost every horse in the world.
