Celtic Britons
The Anglo-Saxon historian Bede, writing in Latin, used the name , with the plural . The "e" vowel in this spelling could be taken from the Anglo-Saxon language's word for the Britons: , also spelled Britt-, Bryt, Brytt-, Bret, and Brit. The Anglo-Saxons probably took this name from the Romano-British. The  was a word used in Britain from the 5th century. Whether the Anglo-Saxons took the name Brett from the Latin name or from a British word of the same meaning is unknown. The Anglo-Saxons must have started using the word Brett by the 6th century. If they had copied the British word at a later time, the word would have had -th- instead of -t-, like the . In that case, the Old English copy would have had -þ- or -ð- in the place of -tt-.