We examine universities and urban growth in pre-industrial Europe using a panel of 2,247 cities from 1000 to 1800 and a staggered difference-in-differences design. Under the maintained identifying assumptions, university establishment is associated with approximately 20 percent higher city population, but estimates are highly heterogeneous. Population gains are strongest in earlier centuries and weaken as universities diffuse, while after 1500 they are concentrated among high-quality universities and commercially connected cities, especially near Atlantic and North Sea trade routes. University establishment is also followed by improved local market access. Overall, universities matter most where academic quality and commercial opportunities are greatest.