December 21: edit
- 1118 - Thomas Becket, Lord Chancellor of England and Archbishop of Canterbury, born. (d. 1170)
- 1596 - Petro Mohyla, Moldovan Orthodox Metropolitan Bishop of Kiev and Galicia, born. (d. 1646)
- 1603 - Roger Williams, English theologian and colonist, born. (d. 1684)
- 1811 - Archibald Campbell Tait, Archbishop of Canterbury, born. (d. 1882)