There is no ‘Spanish Cycle’ to complement any of the branches of the French Lancelot-Grail Cycle. Rather, certain works from the latter population of texts were variously translated, adapted, modified, excerpted, or imitated, most of them anonymously, in Castilian and related dialects, and in Portuguese and Catalan. At the same time, and subsequently, many Arthurian elements and characters widely known in the cultural milieu of the Peninsula were incorporated, in more or less disguised form, into so-called pseudo-Arthurian works.

The earliest Peninsular reference to Arthurian matters is in a work by the Catalan troubador Guiraut de Cabrera, dating from around 1170, and clearly bespeaking Guiraut's knowledge of such well known characters as Erec, Tristan, ‘Yceut’ (Isolde), and ‘Gualvaing’ (Gawain). Guiraut's fastidious analysis of a jongleur's handling of Arthurian material suggests that the matière de Bretagne was at first a prestigious import destined for elite Peninsular audiences. Another early trace of Arthur in a Peninsular source occurs in a brief reference in the Corónicas navarras, dating from the last decade of the twelfth century.

William Entwistle notes the intervention of several important historical personages in the early formation of Peninsular Arthurian tradition. These include Eleanor, daughter of Henry II of England and of Eleanor of Aquitaine, who married into a Spanish house and remained a patroness of troubadours. Further evidence for the reception of Arthurian matter are the copies of several French romances known to have existed in the libraries of King Martin of Aragon (d. 1410), King Duarte of Portugal (d. 1438), and Prince Charles of Viana (d. 1461). Awareness of Arthurian legend and literature is revealed by the work of Alfonso the Learned (d. 1284) and his grandson King Dinis of Portugal (d. 1325), both of whom mention Tristan in their poetry. King Dinis's bastard son Pedro, Count of Barcellos (d. 1354) includes in his Livro das Linhagens a genealogy of English kings adapted from Geoffrey of Monmouth's Latin Chronicle. The Vatican manuscript of the Canzioniere portoghese Colocci-Brancuti contains Lays de Bretanha which confirm a familiarity, among thirteenth-century Galician and Portuguese troubadors, with the matière de Bretagne.