Earliest Halloween customs
The earliest documented customs attributable to Halloween proper grew out of the tandem observances of All Saints Day (November 1), a day of prayer for saints and martyrs of the Church, and All Souls Day (November 2), a day of prayer for the souls of all the dead. Among the practices associated with Halloween during the Medieval period were the lighting of bonfires, evidently to symbolize the plight of souls lost in purgatory, and souling, which consisted of going door-to-door offering prayers for the dead in exchange for "soul cakes" and other treats. Mumming, a custom originally associated with Christmas consisting of parading in costume, chanting rhymes, and play-acting, was a somewhat later addition to Halloween.
Again, however, despite the obvious similarities between old and new,
it may be an exaggeration to say these medieval customs "survived" to the present day, or even that they "evolved" into modern Halloween practices
such as trick-or-treating.