Columba founds Iona
From here Irish monks will take Christianity to Picts and Angles

In 563 the Irish monk Columba and twelve companions landed on the island of Iona off the coast of Scotland and founded a monastery. Iona became a centre of Celtic Christianity, sending missionaries to the Picts and to Northumbria.
Wikipedia (Russian) · Wikipedia (English) · 6th century
Meanwhile around the world (±25 years)
Middle East
- c. 570 Year of the Elephant — 7 years later
Asia
- c. 538 Buddhism reaches Japan — 25 years earlier
- 552 Founding of the First Turkic Khaganate — 11 years earlier
Alive at the time
- Justinian I (aged 81)
- Khosrow I (aged 62)