The exact extent of the direct influence of Irish literature upon the development of other nations is hard to trace, chiefly because the influence of Ireland upon the Continent was at its height at the time when none of the languages of modern Europe except Welsh and Anglo-Saxon had reached a stage at which they might be used for literary purposes, and a Continental literature on which the Irish one might have influence simply did not exist. Its subsequent influence, in the tenth and eleventh centuries, upon Welsh, and through Welsh upon the early Breton literature (now lost) appears to be established; it is usually supposed that its action upon the earliest French compositions was only through the medium of these languages, but it is at least possible that its influence in this case also was more direct. In Merovingian and early Carlovingian times, when French songs were composed, which are now lost but must have preceded the extant chansons de geste, the Irish schools were attracting scholars from the neighbouring countries of Europe; Ireland was sending out a steady stream of "learned men" to France, Germany, and Italy; and it is at least possible that some who knew the Irish teachers realized the merit of the literary works with which some of these teachers must have been familiar. The form of the twelfth-century French romance, "Aucassin and Nicolete," is that of the chief Irish romances, and may well have been suggested by them; whilst the variety of the rhythm and the elaborate laws of the earliest French poetry, which, both in its Northern and Southern form, dates from the first half of the twelfth century, almost imply a pre-existing model; and such a model is more easily traced in Irish than in any other vernacular literature that was then available. It is indeed nearly as hard to suppose that the beautiful literature of Ireland had absolutely no influence upon nations known to be in contact with it, as it would be to hold to the belief that the ancient Cretan civilisation had no effect upon the liter ary development that culminated in the poems of Homer.