The Játvarðar Saga (in full Saga Játvarðar konungs hins helga), is an Icelandicsaga about the life of Edward the Confessor, King of England (1042–1066). It was compiled in the 14th century, in Iceland, using a number of earlier English sources as well as the French Chronicon Universale Anonymi Laudunensis (or a source common with it). It was translated into English in 1894 by G. W. Dasent. Among the various details contained in the saga, there is an account of the origin of an English colony in the Black Sea founded by one "Siward earl of Gloucester" (Sigurðr jarl af Glocestr), a refugee of the Norman Conquest of England.
Ciggaar, Krijnie N. (1974), "L'Émigration Anglaise a Byzance après 1066: Un Nouveau Texte en Latin sur les Varangues à Constantinople", Revue des Études Byzantines, Paris: Institut Français d'Études Byzantines, 32: 301–42, doi:10.3406/rebyz.1974.1489, ISSN0766-5598
Dasent, G. W., ed. (1894), Icelandic Sagas and Other Historical Documents Relating to the Settlements and Descents of the Northmen on the British Isles [4 vols; 1887–94], Rerum Britannicarum Medii Aevi scriptores ; , 3, London: Eyre and Spottiswoode
Fell, Christine (1978), "The Icelandic Saga of Edward the Confessor: Its Version of the Anglo-Saxon Emigration to Byzantium", Anglo-Saxon England, Cambridge: Cambridge University Press, 1: 179–96, ISSN0263-6751
Fell, Christine (1972), "The Icelandic Saga of Edward the Confessor: The Hagiographic Sources", Anglo-Saxon England, Cambridge: Cambridge University Press, 1: 247–58, doi:10.1017/s0263675100000181, ISSN0263-6751