THE extensive studies which during the past fifty years have been carried out by American, British, Dutch, French and German scholars on the influenres exercised by Celtic mythology on the mediaeval literature of the Continent have been confined almost entirely to Motivforschung.1 That it would be worth studying what the Continent learned, through those influences, of the countries from which they originated, of their geography, history and inhabitants, is a suggestion which may be regarded as a relapse into methods of literary research characteristic of nineteenth-century Positivism. Yet it is astonishing that in such a comprehensive work as Gertrude Schoepperle's Tristan and Isolt, a Study of the Sources of the Roman (1913) not a single reference was made to the fact that Gottfried's Tristan is distinguished from the earlier Tristan-tradition by the references made in it to historical Irish place-names2 and to social and cultural conditions in contemporary Ireland, and that these references show that Gottfried had more recent and more definite information of Ireland than that embodied in the Irish influences which can be traced in his sources. The Tristan tradition as a whole is an important source of the development of Continental knowledge of Ireland under Norman influence. The definite references made in the epics of mediaeval France and Germany to chivalresque relations with Ireland have not been investigated either, though it might have been expected that these relations have played an important part in conveying Irish influences to the Continent. The Tristan tradition shows us at its height the connection between Irish literary influence and concrete information on Ireland. An investigation of the development of this connection may offer some contributions to the study of Irish literary influences. It is remarkable that Irish scholars, far from enthusiastically adopting the theory that Ireland was the cradle of basic tendencies of the chivalresque literatures of mediaeval Europe, have emphasized the fundamental weakness of that study, which appears to be based on suggestions rather than facts.3 The investigation of actual references to Ireland and Irish things in mediaeval Continental literature may not lead to such far-reaching conclusions as the study of Irish literary influences, but it rests on a fairly secure basis. We may expect that literary works enshrining Irish influences contain a certain amount of information on Ireland, especially of that period when those influences were actually conveyed to the Continent. It would of course be quite er-