November 2 is All Souls Day in the Western Christian calendar, and dispite the obvious theological, pastoral and personal reasons, it was a late -- post-Civil War certainly -- addition to Universalist consciousness and possibly as late as 1880, when its observation (with other holidays) was considered by the Universalist General Convention for approval.
(Also, most All Souls-named churches in the Unitarian Universalist Association today rest on Unitarian, not Universalist, foundations.)
And the Universalist General Convention did commend it:
It is recommended that the First Sunday of November, in each year, be set apart as All-souls Sunday, for a special celebration of our distinguishing doctrine, the Scriptural truth that all souls are God's children and that finally, by His grace attending them, they will all be saved from the power of sin and will live and reign with Him forever in holiness and happiness.
Perhaps, in this spirit we can recall in prayer the 100 billion or so human beings who have ever lived, the vast majority of whom are now dead.
Since I suspect influential minister Charles H. Leonard had a hand in the commendation resolution, I'll link to the All Souls Day service in the prayerbook from his former parish, the (defunct) Church of the Redeemer, Chelsea, Mass.
Peace to us all.