The origin of the celebration of all saints lies in the Eastern Church:
- A memorial of all martyrs were celebrated on various dates as early as in the 4th century.
- The Byzantine rite still celebrates the Sunday after Pentecost as the Sunday of All Saints.
- The Eastern Syriac liturgy used to celebrate all saints on Friday after Easter.
The feast of all saints is first attested for England and Ireland in the mid 8th century. Its origins perhaps go back to the establishing of a chapel in honor of all saints in St. Peter’s in Rome by Pope Gregory III (731-741). The feast then spread on the continent during the reign of Pope Gregory IV (828-844).
This feast celebrates all the unknown saints who are now in Heaven. Sanctity is within everyone’s reach; through the Communion of Saints each part of the Mystical Body of Christ helps every other to grown in holiness.
Today by your gift we celebrate the festival of your city, the heavily Jerusalem, our mother, where the great array of our brothers and sisters already gives you eternal praise. Towards her, we eagerly hasten as pilgrims advancing by faith, rejoicing in the glory bestowed upon those exalted members of the Church through whom you give us, in our frailty, both strength and good example.Roman Missal; Preface