Stockyards needs to be unlocked first before Fulling Mills becomes accessible.
This technology makes gatherers collect food from Livestock animals 300% faster, making it similar to the gathering speed for crates and an effective food source.
There are several Biblical references to fulling (2 Kings 18:17; Isaiah 7:3 and 36:2; Malachi 3:2; Mark 9:3). The first references to fulling mills are reported in Persia from the 10th century. By the time of the Crusades in the late eleventh century, fulling mills were active throughout the medieval Islamic world, from Islamic Spain and North Africa in the west to Central Asia in the east. They appear to have originated in 9th or 10th century in the Islamic world, either in the Middle East or North Africa. Mechanical fulling was subsequently disseminated into Western Europe through Islamic Spain and Italy in the 11th and 12th centuries.
The earliest known reference to a fulling mill in France, which dates from about 1086, was discovered in Normandy.