ONE COULD GO BACK FURTHER, BUT AD 664 IS A GOOD PLACE TO HALT, BECAUSE IT WAS AN ECLIPSE WITH SIGNIFICANT IMPLICATIONS.
This was the first total solar eclipse to be observed and recorded in England, thee path crossing the northern parts of Ireland and then a band reaching from the present Scottish border down to York. But there is something about it which has been puzzling scholars since 1590, and has yet to be resolved. We know, from modern computations and records in monastic archives from Ireland and across continental Europe, that it happened on 1 May. The puzzle is that the English monasteries recorded it as occurring on 3 May, and we know this was no mere slip of the quill The record was deliberately falsified, and this was not a trivial deceit.
What Happened?
The year 664 is notable for two other events: an outbreak of the bubonic plague, and the Synod of Whitby, where the decision was taken by King Oswy of Northumberland to desert the Celtic Church and take up instead with the Roman Church.
The latter had made incursions into the British Isles from 597, when Saint Augustine and his missionaries arrived and established the first cathedral at Canterbury. Upon this religious conversion hinged the future of the entire British Isles, for it led to the unification of England and the end of paganism.