St. Nilus the Younger as a retreat for the monks who lived in the tufa grottos underneath. The present name of Calabria comes from the duchy of Calabria. Around the year 800, Saracens began invading the shores of Calabria, attempting to wrest control of the area from the Byzantines. This group of Arabs had already been successful in Sicily and knew that Calabria was another key spot. The people of Calabria retreated into the mountains for safety. Although the Arabs never really got a stronghold on the whole of Calabria, they did control some villages while enhancing trade relations with the eastern world. In 918, Saracens captured Reggio (which was renamed Rivà), holding many of its inhabitants to ransom or keeping them prisoners as slaves. It is during this time of Arab invasions that many staples of today's Calabrian cuisine came into fashion: Citrus fruits and eggplants for example. Exotic spices such as cloves and nutmeg were also introduced. Under the Byzantine dominion, between the end of the 9th and the beginning of the 10th century, Calabria was one of the first regions of Italy to introduce silk production to Europe. According to André Guillou, mulberry trees for the production of raw silk were introduced to southern Italy by the Byzantines at the end of the ninth century. Around 1050 the theme of Calabria had 24,000, mulberry trees cultivated for their foliage, and their number tended to expand. At the beginning of the tenth century (circa 903), the city of Catanzaro was occupied by the Muslim Saracens, who founded an emirate and took the Arab name of قطنصار – QaTanSáar. An Arab presence is evidenced by findings at an eighth-century necropolis which had items with Arabic inscriptions. Around the year 1050, Catanzaro rebelled against Saracen dominance and returned to a brief period of Byzantine control. In the 1060s the Normans, under the leadership of Robert Guiscard's brother, Roger I of Sicily, established a presence in this borderland, and organized a government modeled on the Eastern Roman Empire and was run by the local magnates of Calabria. Of note is that the Normans established their presence here, in southern Italy (namely Calabria), 6 years prior to their conquest of England, (see The Battle of Hastings). The purpose of this strategic presence in Calabria was to lay the foundations for the Crusades 30 years later, and for the creation of two Kingdoms: