A time to print, a time to reform

The public mechanical clock and movable type printing press were arguably the most important and complex technologies of the late medieval period. We posit that towns with clocks became upper-tail human capital hubs—clocks required extensive technical know-how and fine mechanical skill. This meant that clock towns were in position to adopt the printing press soon after its invention in 1450, as presses required a similar set of mechanical and technical skills to operate and repair. A two-stage analysis confirms this conjecture: we find that clock towns were 34–40 percentage points more likely to also have a press by 1500. The press, in turn, helped facilitate the spread of the Protestant Reformation. A three-stage instrumental variables analysis indicates that the press influenced the adoption of Protestantism, while the clock’s effect on the Reformation was mostly indirect. Our analysis therefore suggests that the mechanical clock was responsible – directly and indirectly – for two of the most important movements in the making of the modern world: the spread of printing and the Reformation.