|Covid-19|Cadoc, abbot of Llancarfan (Wales), settles in Weedon and is made bishop (approximate date).
August 22 – Columba reports seeing the Loch Ness Monster at the River Ness (according to the "Life of St. Columba").
Tulum, Maya walled city, on the Yucatán Peninsula (modern Mexico) is first mentioned on a stele inscription.
Samson of Dol, one of seven founder saints of Brittany, attends a council in Paris and witnesses several royal decrees (approximate date).
Hermenegild, Visigoth prince (approximate date)
Li Baiyao, Chinese official and historian (d. 647)
Gao Bainian, crown prince of Northern Qi (b. 556)
Tudwal, Breton monk and saint (approximate date)
Year 564 (DLXIV) was a leap year starting on Tuesday (link will display the full calendar) of the Julian calendar. The denomination 564 for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years.