All Saints Day Masses

From the first centuries after Christ, Christians who died a martyr’s death were considered saints, who live in God’s presence forever. Every year, on the anniversary of the martyrs’ deaths, Christians would visit their tombs and celebrate the Eucharist. This practice grew throughout the centuries to include remembering other outstanding Christians on the days they died. Soon the entire calendar was filled with memorials of the saints. In the ninth century, Pope Gregory IV designated November 1 as the day to remember all the saints living in God’s presence.

Fr James Martin explains the connection between All Saints Day and Halloween:
https://youtu.be/JJsokZ6Y2x8 
 

Collect Prayer from the solemnity of All Saints

Let us pray today.
     Almighty ever-living God,
     By whose gift we venerate
in one Celebration
    the merits of all the Saints,
    bestow on us, we pray,
    through the prayers
of so many intercessors,
    an abundance of
the reconciliation with you
    for which we earnestly long.
    Through our Lord Jesus Christ,
             your Son, ho lives and reigns with you
in the unity of the Holy Spirit,
    one God, for ever and ever.