At a Glance
December 21
Observances & Celebrations
Commemorative holidays, national days, religious feasts, and international traditions observed on this date.
Religious observance
Feast of December 21 (Eastern Orthodox liturgics)
Religious observance
Feast of O Oriens
Religious observance
Feast of Peter Canisius
Religious observance
Feast of Thomas the Apostle
Observance
Armed Forces Day (Philippines)
Philippines
Observance
Forefathers' Day (Plymouth, Massachusetts)
Observance