Picardie Towns, Citadels of Catholicism. In the last third of the XVIth century, Picardie was one of the provinces siding the more strongly with the Ligue. What were the reasons of this early, massive and lasting involvement ? If the motives underlying this attitude are, obviously, complex, the primacy of religion looks all the same undoubtable. Indeed, to understand the call to arms of the years 1580-1590, it is essential to have a clear view of the extend of the fight the towns of Picardie waged at a very early date against the implementation of Reformation within their walls. The various means they put into practice, essentially since the 1560s, were indeed very efficient, to such an extent that Protestantism entered a phase of recessio...