Gildas was a 5th or early 6th-century monk whose colourful accounts of the early post-Roman period form one of the few sources of written history for this period of British history. The primary work for which Gildas is known is De Excidio et Conquestu Britanniae, which translates roughly as 'The Ruin of Britain'.
The trouble with Gildas's writing is that it was never intended as history, at least not history as we know it. It is more along the lines of a polemic against the evils and abuses of the leading church and secular figures of the early 6th century. Gildas tries to explain some background of how these abuses came to be, and it is this background narrative that provides the historical 'meat' of Gildas's writing. Gildas relied on oral traditions, and his own biases, and does not attempt to lay down a chronology of events.
Gildas is scathing in his condemnation of clerics, but even more so in his criticism of the British kings during his lifetime, particularly those in Wales and the south-west of modern England. He seems particularly upset that these kings pay homage to an unnamed, but presumably pagan, ruler. Now, criticizing a ruling king is a risky business, so Gildas veils his writings as metaphors and veiled allusions based on Biblical tales. Gildas saw the devastation wrought by Germanic invaders as the wrath of God visited upon the British for the sins of their churchmen and kings.
Who was Gildas?
Gildas's own origins are obscure; he may have been Welsh, or Irish, but there is little solid evidence for either. Later tales suggest that he was the son of a Pictish king, but no contemporary sources support that hypothesis. In truth, we know little of the man beyond his name. He himself says that he was born in the year of the Battle of Badon Hill (Mons Badonicus, or Mount Badon).
Unfortunately, we are on shaky ground about this battle; the date is commonly assumed to be between 470 - 520 AD, at an unknown location. Gildas may have died around the year 570 AD, but even there we are on uncertain ground. He was obviously well educated, and his Latin is evidence of a scholarly mind.
Gildas first rose to prominence in the writings of the Venerable Bede. Bede, also a monk, wrote his Ecclesiastical History of the English People in the early 8th century. In it, he acknowledges his debt to Gildas for much of his historical material covering the 5th and 6th centuries.
As far as historical accuracy goes, the accounts of Gildas must be regarded with great caution, but nevertheless his writing remains one of the few early written histories of Britain, and as such has remained a popular reference point in an age with few written records.
Related:
Bede
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