Silk was, however, the only textile material which was a very important ware in its raw form. The culture of the silkworm, which had been carried on for centuries in China, but so far as possible had been kept a secret from other peoples, spread gradually to the West and was introduced into Europe by the Emperor Justinian in the sixth century. The Arabians introduced mulberry plantations and the raising of silkworms into Sicily and Spain, and the culture thrived so far as to leave a surplus for export after supplying the home manufactures. Christian peoples, however, did not succeed so well in the culture; France could as yet furnish no appreciable quantity of raw silk, and the output in Italy was unsatisfactory both in respect to quality and quantity. The growing silk manufacture in Europe had therefore to meet its deficiency by trade with the East, getting part of its supply of raw material from China and Persia, but the bulk from the countries about the Caspian Sea. =94. Textile imports; exports from Europe.=—Among manufactures imported from the East textiles held the most important place. Europe was strong enough in the manufacture of linen and woolen goods to export them in considerable quantities to Asia, but it lacked in the manufacture of cotton and silk not only raw material but the technical skill to compete with the artisans of the East; and imported large quantities of finished cloth. Dignitaries of the church and the merchant princes of the late Middle Ages demanded for clothing and for furniture fabrics of finer quality and of greater quantity than the looms established by the Mohammedans in Spain and Sicily could supply, and sought them chiefly in the countries bordering the eastern end of the Mediterranean. From this district came a great variety of silks, woven often as brocades with gold or silver threads, and the early types of velvet and satin. Silk goods formed the chief but not the sole constituent of the textile imports; with them came fine cottons from India, cloth made from the hair of camels and other animals, and linen from Egypt and Syria, which surpassed all of western make. Europe depended also on the East for fine china and glass. Before the end of the Middle Ages the Italian silk manufacture had grown strong enough to turn the tide, and to export to the East. Through the greater part of this period, however, the only European textiles exported to Asia were the woolens and common linens which were produced in England, Flanders, and other of the more advanced countries. Besides these manufactures the main exports consisted of raw materials: wool, hides, metals (gold, silver, and tin), and food stuffs.