This study documents the boom in Europe's imports from Asia and the Americas between 1500 and 1800 and explores its causes. There was no commodity-price convergence between continents, suggesting that declining trade barriers were not the cause of the boom. Thus, it must have been caused by some combination of European import demand and foreign export supply. The behavior of the relative price of foreign importables in European cities should tell us which mattered most and when: we provide the evidence and offer a model which is used to decompose the sources of Europe's overseas trade boom.