The establishment of George as a popular saint and protective giant[44] in the West, that had captured the medieval imagination, was codified by the official elevation of his feast to a festum duplex[45] at a church council in 1415, on the date that had become associated with his martyrdom, 23 April. There was wide latitude from community to community in celebration of the day across late medieval and early modern England,[46] and no uniform "national" celebration elsewhere, a token of the popular and vernacular nature of George's cultus and its local horizons, supported by a local guild or confraternity under George's protection, or the dedication of a local church. When the English Reformation severely curtailed the saints' days in the calendar, Saint George's Day was among the holidays that continued to be observed.