Corea, though unknown even by name in Europe until the sixteenth century, was the subject of description by Arab geographers of the middle ages. Before the peninsula was known as a political unit, the envoys of Shinra, one of the three Corean states, and those from Persia met face to face before the throne of China. The Arab merchants trading to Chinese ports crossed the Yellow Sea, visited the peninsula, and even settled there. The youths of Shinra, sent by their sovereign to study the arts of war and peace at Nanking, the mediæval capitol of China, may often have seen and talked with the merchants of Bagdad and Damascus. The Corean term for Mussulmans is hoi-hoi , "round and round" men. Corean art shows the undoubted influence of Persia.