In the close of the heroic literature of Iceland a number of general causes are to be found at work. The period of the Sagas comes to an end partly by a natural progress, culmination, and exhaustion of a definite form of literary activity, partly through external influences by which the decline is hastened. After the material of the early heroic traditions had been all used up, after the writers of the thirteenth century had given their present shapes to the stories of the tenth and the eleventh centuries, two courses were open, and both courses were taken. On the one hand the form of the Saga was applied to historical matter near the writer's own time, or actually contemporary, on the other hand it was turned to pure fiction. The literature divides into history and romance. The authentic history, the Sturlung cycle in particular, is the true heir and successor of the heroic Saga. The romantic Sagas are less intimately related to the histories of Njal or Gisli, though those also are representative of some part of the essence of the Saga, and continue in a shadowy way something of its original life. The Northern literatures in the thirteenth century were invaded from abroad by the same romantic forces as had put an end to the epic literature of France; translations of French romances became popular, and helped to change the popular taste in Norway and Iceland. At the same time the victory of Romance was not entirely due to these foreigners; they found allies in the more fanciful parts of the native literature. The schools of Northern prose romance, which took the place of the older Sagas, were indebted almost as much to the older native literature as to Tristram or Perceval; they are the product of something that had all along been part, though hardly the most essential part, of the heroic Sagas. The romantic story of Frithiof and the others like it have disengaged from the complexity of the older Sagas an element which contributes not a little, though by no means everything, to the charm of _Njála_ and _Laxdæla_. The historical work contained in the _Sturlunga Saga_ is a more comprehensive and thorough modification of the old form. Instead of detaching one of the elements and using it in separation from the rest, as was done by the author of _Frithiof_, for example, the historian of the Sturlungs kept everything that he was not compelled to drop by the exigencies of his subject. The biographical and historical work belonging to the _Sturlunga Saga_ falls outside the order to which _Njal_ and _Gisli_ belong; it is epic, only in the sense that a history may be called epic. Nevertheless it is true that this historical work shows, even better than the heroic Sagas themselves, what the nature of the heroic literature really is. In dealing with a more stubborn and less profitable subject it brings out the virtues of the Icelandic form of narrative.