THE VIGIL OF ALL SAINTS

In the eighth century the Gregorian Sacramentary indicated among the common Masses without a date:  The Mass in honor of All Saints.  Fixed in the following century on November 1, it became The Mass of All Saints Day that is now prepared for by that of a vigil.  Thus today is the Eve of All Saints, otherwise known as All Hallows Eve, that is Hallows Eve, or now more commonly,  Halloween.