In the 1830s the British and American economies were hit by a series of shared macroeconomic shocks. This paper investigates the role of markets for America's State bonds in Britain and the USA during and between the crises in 1837, 1839, and 1842.There is strong evidence that the crises in 1839 and 1842 originated in the USA and spread to Britain. There is also strong evidence that credit markets for American state bonds were tighter in the USA than in London between 1839 and 1842.