This article explores the development of market integration within the Baltic Sea region and with England, from the 1840s to the late 1880s. It exploits two new datasets on grain prices. The degree of market integration is estimated using a wavelet variant of dynamic factor analysis that takes account of both time and distance. Additionally, we use the London corn market as the benchmark for the degree of market integration. Our results show that the role of distance disappeared in the wheat and rye, but not in the oats and barley trade, as the Baltic Sea Region became integrated into the Atlantic economy.