From the Martyrs to All the Holy Dead

All Saints is the Western feast, kept on 1 November, honouring every saint in heaven, the celebrated and the anonymous alike. It grew out of the early commemoration of martyrs: local churches kept the anniversaries of their own witnesses, and as the number outran the calendar a single collective feast emerged to embrace them all, later widened to include all the holy dead, not only those who died for the faith. A general feast of all martyrs is attested in the Christian East by the fourth century.

The Roman date has a documented origin. Pope Boniface IV dedicated the Pantheon in Rome as a church of Mary and the martyrs in the early seventh century, on 13 May; the shift to 1 November is associated with the eighth- and ninth-century Frankish church and its formal extension by Pope Gregory IV. Whether the November date was chosen to overlay the Celtic Samhain is argued both ways and cannot be settled from the sources; the May and November commemorations both predate any securely dated contact between them.