A possible depiction of the ancient Wag Festival
The Wag Festival was an ancient Egyptian festival that supposedly took place in late August and was dedicated to the death of Osiris, the Egyptian god of wine, death, and the underworld, and honoring the souls of the deceased on their journey in the afterlife. This festival followed the Wepet-Renpet, but its date changed according to the lunar calendar. It is one of the oldest festivals celebrated by the Egyptians and, like Wepet-Renpet, first appears in the Old Kingdom.
During this festival, people would make small boats out of paper and set them toward the west on graves to indicate Osiris' death and people would float shrines of paper on the waters of the Nile for the same reason.
This festival is featured in the 1993 animated TV special The Halloween Tree, in which it is said to be when trick-or-treating originated, as, while the spirits and bodies of some, or maybe just one, of the families' deceased relatives feasted with the living, the spirits of those who did not have families wandered the streets of the towns and villages that celebrated the Wag Festival. However, the living were considerate enough to leave food and drink on the front porches of their homes for those wandering souls.