Felt is believed to have been discovered by the nomadic tribes of Asia, who made tents and garments by felting sheep's wool. One of its early uses in headwear was in the Roman 'petasus', a narrow-brimmed skull-cap which was the general head covering of the populace. Slaves were not permitted to wear it, and a ceremony in connection with making the slave a free man was the presentation of the citizen's petasus.