1. Alcuin's thought seems to have influenced the regional councils of 813. One notes the strong similarity of his language to that of the capitularies, especially the expression, “not to blush before a priest in confessing your sins.” At the minimum, one could say that his influence was indirect, transmitted by his former pupils, who at the time of these councils, were in positions of leadership.
2. On the subject of epistolary genre in general, cf. Constable G. , Letters and Letter-Collections, Typologie des Sources du Moyen Âge Occidental 17 (Turnhout, 1976). For Alcuin's letters specifically, cf. E. Dümmler in MGH Ep. 4 and Sickel Th. , Alkuinstudien.