Today is All Saints Day!
Another name for today is All Hallows Day - which is where we get the turn "Halloween" for the "Eve of All Hallows Day."
One of the earliest mentionings of this solemnity (feast day) comes to us from St. Ephrim the Syrian from a sermon of his in 373 AD.
The date of November 1st was made official by Pope Gregory III as a holy day in Rome - and was extended to the whole Church by Pope Gregory IV.
All Hallows Eve - or Halloween - is October 31st. This is a secular celebration.
All Hallows Day - or All Saints Day - is November 1st. This is a holy day of obligation. We celebrate all the saints who are in Heaven.
All Souls Day - is November 2nd. This day is not a holy day of obligation, but is a Catholic day for remembering and praying for those souls who have gone before us and may still be in Purgatory.
Sources:
Richert, Scott P. (2020, August 27). All Saints Day. Retrieved from https://www.learnreligions.com/what-is-all-saints-day-542459
https://www.catholic.org/saints/allsaints/
