Today Is November 1

Today is All Saints' Day,  a Christian solemnity celebrated in honor of all the saints of the church, whether they are known or unknown.

Below is All Saints' Day at a cemetery in Gniezno, Poland, the picture shows flowers and candles placed to honor deceased relatives. 

By Diego Delso, Wikipedia

In 609 Pope Boniface IV converted the Roman Pantheon into a Catholic church dedicated to the Virgin Mary and all martyrs. By the 7th century the commemoration of martyrs for the faith had become widespread and as time went on these celebrations came to include not only the martyrs but all saints. 

In 837 Pope Gregory IV established the first celebration of All Saints' Day on November 1st to honor the saints, choosing the first day of November to counter a Celtic festival of the dead, known as Samhain celebrated the night before. However the festival did not die out and in medieval Britain it became known as All Hallows (All Saints) Eve, and later its Scottish equivalent Halloween became more widely used.