Offa a oa roue Mercia eus 757 betek e varv e 796. Mab e oa da Thingfrith ha diskennad da Eowa, breur Penda Mercia. Anvet e voe da roue goude muntr Æthelbald hag ur brezel diabarzh, ma faezhas Beornred. E derou e ren eo gwirheñvel e oa ret dezhañ startaat e c'halloud war pobloù ar Midlands evel ar Hwicce pe ar Magonsæte. Goude 762 e c'hounezas kontrol Rouantelezh Kent a oa bet gwanaaet gant trubuilhoù diabarzh hag e 771 e kouezhas Rouantelezh Sussex dindan e veli, daoust ma chomas diasur e aoutroniezh en div vro-se. E 780 e astennas beli Mercia war an darn vrasañ eus su bro-Saoz. Kevreañ a reas gant Beorhtric Wessex a zimezas e verc'h Eadburh. E penn East-Anglia ez eas ha lakaat a reas he roue Æthelberht II East-Anglia da vezañ dibennet, marteze peogwir e oa en em savet outañ.
Ur roue kristen e oa Offa, met dizemglev a oa etre an Iliz hag eñ, ha dreist-holl gant Jaenberht, arc'heskob Canterbury. Kendrec'hiñ a reas ar pabAdrian Iañ da sevel un arc'heskopti nevez e Lichfield
Keynes, Simon; Lapidge, Michael (2004). Alfred the Great: Asser's Life of King Alfred and other contemporary sources. Penguin Classics. ISBN 0-140-44409-2.
Swanton, Michael (1996). The Anglo-Saxon Chronicle. New York : Routledge. ISBN 0-415-92129-5.
Whitelock, Dorothy (1968). English Historical Documents v. 1 c. 500–1042. London : Eyre & Spottiswoode.
Andonioù an eil renk
Abels, Richard, "Trinoda Necessitas", in Lapidge, Michael (1999). The Blackwell Encyclopaedia of Anglo-Saxon England. Oxford : Blackwell Publishing. ISBN 0-631-22492-0.
Blackburn, Mark & Grierson, Philip, Medieval European Coinage. Cambridge: Cambridge University Press, reprinted with corrections 2006. ISBN 0-521-03177-X
Blair, John (2006). The Church in Anglo-Saxon Society. Oxford : Oxford University Press. ISBN 0199211175.
Brown, Michelle P.; Farr, Carole A. (2001). Mercia: An Anglo-Saxon kingdom in Europe. Continuum. ISBN 0-8264-7765-8.
Campbell, James (2000). The Anglo-Saxon State. Hambledon and London. ISBN 0-85285-176-7.
Campbell, John; John, Eric & Wormald, Patrick (1991). The Anglo-Saxons. Penguin Books. ISBN 0-14-014395-5.
Featherstone, Peter, "The Tribal Hidage and the Ealdormen of Mercia", in Brown, Michelle P.; Farr, Carole A. (2001). Mercia: An Anglo-Saxon kingdom in Europe. Continuum. ISBN 0-8264-7765-8.
Fletcher, Richard (1989). Who's Who in Roman Britain and Anglo-Saxon England. Shepheard-Walwyn. ISBN 0-85683-089-5.
Gannon, Anna (2003), The Iconography of Early Anglo-Saxon Coinage: Sixth to Eighth Centuries, Oxford: Oxford University Press, ISBN 0199254656.
Hunter Blair, Peter (1977), An Introduction to Anglo-Saxon England (2nd ed.), Cambridge: Cambridge University Press, ISBN 0-521-29219-0
Hunter Blair, Peter (1966). Roman Britain and Early England: 55 B.C. – A.D. 871. New York : W.W. Norton & Company. ISBN 0-393-00361-2.
Keynes, Simon, "Cynethryth", in Lapidge, Michael (1999). The Blackwell Encyclopaedia of Anglo-Saxon England. Oxford : Blackwell Publishing. ISBN 0-631-22492-0.
idem, "Mercia", in Lapidge, Michael (1999). The Blackwell Encyclopaedia of Anglo-Saxon England. Oxford : Blackwell Publishing. ISBN 0-631-22492-0.
idem, "Offa", in Lapidge, Michael (1999). The Blackwell Encyclopaedia of Anglo-Saxon England. Oxford : Blackwell Publishing. ISBN 0-631-22492-0.
idem, "Mercia and Wessex in the Ninth Century", in Brown, Michelle P.; Farr, Carole A. (2001). Mercia: An Anglo-Saxon kingdom in Europe. Continuum. ISBN 0-8264-7765-8.
Keynes, Simon; Michael Lapidge (2004). Alfred the Great: Asser's Life of King Alfred and other contemporary sources. Penguin Classics. ISBN 0-140-44409-2.
Kirby, D.P. (1992). The Earliest English Kings. London : Routledge. ISBN 0-415-09086-5.
Lapidge, Michael, "Alcuin of York", in Lapidge, Michael (1999). The Blackwell Encyclopaedia of Anglo-Saxon England. Oxford : Blackwell Publishing. ISBN 0-631-22492-0.
Lapidge, Michael (1999). The Blackwell Encyclopaedia of Anglo-Saxon England. Oxford : Blackwell Publishing. ISBN 0-631-22492-0.
Nelson, Janet, "Carolingian Contacts", in Brown, Michelle P.; Farr, Carole A. (2001). Mercia: An Anglo-Saxon kingdom in Europe. Continuum. ISBN 0-8264-7765-8.
Stafford, Pauline, "Political Women in Mercia, Eighth to Early Tenth Centuries", in Brown, Michelle P.; Farr, Carole A. (2001). Mercia: An Anglo-Saxon kingdom in Europe. Continuum. ISBN 0-8264-7765-8.
Williams, Gareth, "Mercian Coinage and Authority", in Brown, Michelle P.; Farr, Carole A. (2001). Mercia: An Anglo-Saxon kingdom in Europe. Continuum. ISBN 0-8264-7765-8.
idem, "Military Institutions and Royal Power", in Brown, Michelle P.; Farr, Carole A. (2001). Mercia: An Anglo-Saxon kingdom in Europe. Continuum. ISBN 0-8264-7765-8.
Wormald, Patrick, "The Age of Offa and Alcuin", in Campbell, John; John, Eric & Wormald, Patrick (1991). The Anglo-Saxons. Penguin Books. ISBN 0-14-014395-5.
Wormald, Patrick; Bullough, D. & Collins, R. (1983). Ideal and Reality in Frankish and Anglo-Saxon Society. Oxford : B. Blackwell. ISBN 0-631-12661-9..
Yorke, Barbara (1990). Kings and Kingdoms of Early Anglo-Saxon England. London : Seaby. ISBN 1-85264-027-8.
Worthington, Margaret, "Offa's Dyke", in Lapidge, Michael (1999). The Blackwell Encyclopaedia of Anglo-Saxon England. Oxford : Blackwell Publishing. ISBN 0-631-22492-0.
eadem, "Wat's Dyke", in Lapidge, Michael (1999). The Blackwell Encyclopaedia of Anglo-Saxon England. Oxford : Blackwell Publishing. ISBN 0-631-22492-0.