About Orthodox All Saints Day
In the Eastern Orthodox Church, All Saints Day is observed on the first Sunday after Pentecost. This means that All Saints’ Day in Eastern Orthodox traditions usually falls between early June and early July.
The Feast of All Saints was officially begun in A.D. 609 by Pope Boniface IV when he consecrated the Parthenon in Rome to the Virgin Mary and all Christian martyrs. The roots of the holiday, however, are even older. In the early years of Christianity, Christians would remember a martyr on the anniversary of their death by gathering at the place where the martyr died. When multiple martyrs died in one place or at one time, larger groups of Christians and larger celebrations emerged.
Eventually, the church felt that, although every martyr needed to be remembered, there were too many martyrs and saints to give each their own feast day. So, a common day was needed where all martyrs and saints would be celebrated. In the seventh century, Pope Boniface IV finally made the day remembering all martyrs official.
The original date that Pope Boniface IV chose would correspond to May 13th on the current Gregorian calendar. This day was a popular pagan holiday, the three day Feast of the Lemures. During the Lemures or Lemuria festival, all the malevolent and restless dead were mollified. This emphasis on the dead in both holidays made it easy for one to supplant the other.
Western Churches observe All Saints Day on November 1st.