 As a gauge of the importance of the town, by the 1770s Leeds merchants were responsible for 30% of the country's woollen exports, valued at £1,500,000 when 70 years previously Yorkshire accounted for only 20% of exports.Weaving was introduced into West Yorkshire in the reign of Edward III, and Cistercians, such as at Kirkstall, were certainly engaged in sheep farming.Leland (date) records the organised trading of cloth on the bridge over the Aire, at the foot of Briggate, at specified times and under set conditions.