of the region as a horse-breeding land, and partially due to the cultural influences related to the Islamic conquest of the Iberian peninsula between the 8th and 15th centuries. The origins of the medieval war horse are obscure, although it is believed they had some Barb and Arabian blood through the Spanish Jennet, a forerunner to the modern Friesian and Andalusian horse. It is also possible that other sources of oriental bloodstock came from what was called the Nisaean breed (possibly akin to the Turkoman horse) from Iran and Anatolia, another type of oriental horse brought back from the Crusades. "Spanish" horses, whatever their breeding, were the most expensive. In fact, in Germany the word spanjol became the term for quality war horses. However, German literary sources also refer to fine horses from Scandinavia. France also produced good war horses. Some scholars attribute this to the strong Feudal society there, but an equally probable explanation is the historic influence of the Roman horse breeding traditions preserved by the Merovingians, combined with the addition of valuable Spanish and oriental bloodstock captured in the wake of the victory of Charles Martel over the Islamic Umayyad invaders at the Battle of Tours in 732. Following this battle, the Carolingians began to increase their heavy cavalry, which resulted in the seizure of land (for fodder production), and a change in tribute payment from cattle to horses. As the importance of horse breeding to successful warfare was realized, planned breeding programs increased. Many changes were due to the influence of Islamic culture through both the Crusades and the Moorish invasions of Spain; the Arabs kept extensive pedigrees of their Barb and Arabian horses via an oral tradition. Some of the earliest written pedigrees in recorded European history were kept by Carthusian monks, who were among those who bred the Spanish Jennet. Because they could read and write, thus kept careful records, monastics were given the responsibility for horse breeding by certain members of the nobility, particularly in Spain. In England, a common source of warhorses were the wild moorland ponies, which were rounded up annually by horse-breeders, including the Cistercians, for use as campaign riding horses, or light cavalry; one such breed was the Fell pony, which had similar ancestry to the Friesian horse. It is also hard to trace what happened to the bloodlines of destriers when this type seems to disappear from record