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[Arthurian] Northern monk who lived in the first half of the sixth century. He is the author of De Excidio Britanniae ("On the Ruin of Britain"), usually dated to the 530-40's. For the most part it is a condemnation of British kings and church leaders of his own time. The prelude, however, is an outline of British "history" from the first century onward. His goal is not history but rather a list of the misdeeds of his own people that led to the invasion by the Saxons. Arthur is not mentioned in this book. Rather, it deals with a set of events that would lead to Arthur's legendary rise as a temporary saviour-figure. Gildas claims the Saxons were invited in as mercenaries against the Picts by a ruling council and a superbus tyrannus ("leading ruler"), possibly a translation of the Briton title "high king." Bede and most later writers assume this personage to be Vortigern. Gildas tells how the Saxons swarmed into Britain, made excessive demands and then, when the demands were not met, rose up and...
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gilda, gildae
n. f. guild; association; guild meeting; guild-house; 

See more at Wikipedia.org...

[Arthurian] Northern monk who lived in the first half of the sixth century. He is the author of De Excidio Britanniae ("On the Ruin of Britain"), usually dated to the 530-40's. For the most part it is a condemnation of British kings and church leaders of his own time. The prelude, however, is an outline of British "history" from the first century onward. His goal is not history but rather a list of the misdeeds of his own people that led to the invasion by the Saxons. Arthur is not mentioned in this book. Rather, it deals with a set of events that would lead to Arthur's legendary rise as a temporary saviour-figure. Gildas claims the Saxons were invited in as mercenaries against the Picts by a ruling council and a superbus tyrannus ("leading ruler"), possibly a translation of the Briton title "high king." Bede and most later writers assume this personage to be Vortigern. Gildas tells how the Saxons swarmed into Britain, made excessive demands and then, when the demands were not met, rose up and...
Read more...

gilda, gildae
n. f. guild; association; guild meeting; guild-house;