This article surveys the monetary history of Koryŏ from the eleventh to the thirteenth century. During the first century of the dynasty, Koryŏ was at war with the Liao, prohibited trade with the enemy and pursued a policy of protecting its metal reserves. During the ban on metallic coins, rice and cloth served as commodity monies, ensuring price stability in a phase of sustained growth of the rural economy. A second phase began after the victory over the Liao in 1018. Backed by military strength, the government issued iron, bronze and silver currencies to facilitate international trade. The Koryŏ ‘silver vase’ currency, which circulated for three centuries, partly bridges the ‘black hole’ in East Asian monetary history from the Late Tang to the Ming period. The intrinsic value of the metallic currencies in conjunction with state issuance provided monetary stability. In turn monetary instability characterised the late Koryŏ, when the country came under the influence of the Mongol Yuan. The destabilising effect brought about by the introduction of Yuan paper money demonetarised the economy. By framing monetary history within a wider perspective of struggles for sovereignty and political hegemony, the article allows a better understanding of domestic and regional dynamics in East Asia.