Cotton is a cellulose fibre of vegetable origin. It has a fairly long staple and can thus be spun into very fine thread. It is hard-wearing and takes colour well. However it was not grown in Europe in period, but was imported from the Middle East:
"Arab merchants brought cotton cloth to Europe about 800 A.D.. When Columbus discovered America in 1492, he found cotton growing in the Bahama Islands. By 1500, cotton was known generally throughout the world".