Question: Which battle taking place in 7th century England was the result of peace overtures from Augustine's English mission by the Synod of Chester where the armies of the combined Welsh kingdoms of Powys and Rhôs were virtually annihilated?
Sentence (from "Synod of Chester"): The Synod of Chester (Medieval Latin: "Sinodus Urbis Legion(um)") was an ecclesiastical council of bishops held in Chester in the late 6th or early 7th century.
Relevant evidence: Yes