Commemorations of all saints and martyrs were held by several churches on various dates, mostly in springtime. In 4th-century Roman Edessa it was held on 13 May, and on 13 May 609, Pope Boniface IV re-dedicated the Pantheon in Rome to “St Mary and all martyrs”. This was the date of Lemuria, an ancient Roman festival of the dead.n the 8th century, Pope Gregory III (731–741) founded an oratory in St Peter’s for the relics “of the holy apostles and of all saints, martyrs and confessors”. Some sources say it was dedicated on 1 November, while others say it was on Palm Sunday in April 732. By 800, there is evidence that churches in Ireland and Northumbria were holding a feast commemorating all saints on 1 November. Alcuin of Northumbria, a member of Charlemagne’s court, may then have introduced this 1 November date in the Frankish Empire. In 835, it became the official date in the Frankish Empire.