Despite being credited with many of the defining inventions of the early modern era, China failed to develop in line with Western Europe at the start of the 19th century. This column suggests that one reason for this was that China’s economy was more fragmented than that of Europe. Using Chinese monthly grain prices from 1740-1820 and grain price panels from Western Europe, it shows that in terms of market integration, the Great Divergence was well under way decades before the start of the 19th century.