 In addition, merchants began to form their own communities and began to exercise economic power and great wealth even though Japan was dominated by a feudal-military system led by warrior samurais and daimyos who exercised great control over various competing semi-autonomous domains across the Japanese archipelago.In the middle of the 12th century, Chinese coins began to flow into Japan and were beginning to be used as a form of currency.Coins became widespread by the 13th century as the use of the coins was spread among commoners and the Kamakura Shogunate government and imperial court, which initially disapproved of their use, but eventually accepted the used of the coins.