AbstractThis article analyses the biggest pilgrimage event of the Napoleonic era, showing how Catholics used imperial opportunities and imperial loopholes to progress on their path toward religious revival. In September 1810, more than 200,000 pilgrims rushed to the small provincial city of Trier to venerate one of Christianity's most important relics, the Holy Coat of Jesus. This pilgrimage could take place and grow to such gigantic dimensions because both clerical elites and laypeople deftly navigated territorial frameworks created by the Napoleonic state. In the Rhenish borderlands to which Trier belonged, French hegemony enabled the return of the relic to the city in the first place, but pilgrims subsequently exploited the malleability of public order that also characterized imperial governance. The great pilgrimage of 1810 represented neither a form of exclusively top-down mobilization orchestrated by the church and controlled by the state, nor an act of overt, politicized opposition – even as state officials, in turn, proved undeniably hostile to pilgrim mobility and ‘superstition’. The article therefore argues that, in the more peaceful parts of Napoleon's empire, pilgrims and pilgrimage organizers accelerated post-revolutionary Catholic renewal by using that empire rather than either resisting or collaborating with it.