Between thirty and forty poets of Spanish extraction are known to have written Provençal poetry. Guillem de Tudela of Navarre wrote the first part of the _Chanson de la Croisade albigeoise_; Serveri de Gerona wrote didactic and devotional poetry, showing at least ingenuity of technique; Amanieu des Escas has left love letters and didactic works for the [121] instruction of young people in the rules of polite behaviour. But the influence of Provençal upon the native poetry of Spain proper was but small, in spite of the welcome which the troubadours found at the courts of Castile, Aragon, Leon and Navarre. Troubadour poetry required a peaceful and an aristocratic environment, and the former at least of these conditions was not provided by the later years of Alfonso X. Northern French influence was also strong: numerous French immigrants were able to settle in towns newly founded or taken from the Moors. The warlike and adventurous spirit of Northern and Central Spain preferred epic to lyric poetry: and the outcome was the _cantar de gesta_ and the _romance_, the lyrico-narrative or ballad poem. This was not the course of development followed either in the Eastern or Western coasts of the peninsula. Catalonia was as much a part of the Provençal district as of Spain. To the end of the thirteenth century Catalonian poets continued to write in the language of the troubadours, often breaking the strict rules of rime correspondence and of grammar, but refusing to use their native dialect. Religious poems of popular and native origin appear to have existed, but even the growth of a native prose was unable to overcome the preference for Provençal in the [122] composition of lyrics. Guiraut de Cabreira is remembered for the 213 lines which he wrote to instruct his _joglar_ Cabra; Guiraut upbraids this performer for his ignorance, and details a long series of legends and poems which a competent _joglar_ ought to know. Guiraut de Calanso wrote an imitation of this diatribe. The best known of the Catalonian troubadours is Raimon Vidal of Besadun, both for his _novelas_ and also for his work on Provençal grammar and metre, _Las rasos de trobar_,[33] which was written for the benefit of his compatriots who desired to avoid solecisms or mistakes when composing. "For as much as I, Raimon Vidal, have seen and known that few men know or have known the right manner of composing poetry (trobar) I desire to make this book that men may know and understand which of the troubadours have composed best and given the best instruction to those who wish to learn how they should follow the right manner of composing.... All Christian people, Jews, Saracens, emperors, princes, kings, dukes, counts, viscounts, vavassors and all other nobles with clergy, citizens and villeins, small and great, daily give their minds to composing and singing.... In this science of composing the troubadours are gone astray and I will tell you wherefore.