This thirteen-volume series, which first appeared between 1914 and 1965, is an extensive collection of the pre-thirteenth-century charters and related records of Yorkshire, which had previously remained largely unpublished. The first three volumes were edited by William Farrer (1861–1924), after whose death Charles Travis Clay (1885–1978) took up the task. The series was well respected for the quality of Farrer's editing, which was surpassed only by that of Clay in the later volumes. The lack of an index was considered by many reviewers to be the only shortcoming to Farrer's work, and so the present volume, a thorough index to the first three volumes, was published in 1942. Assisted by his niece, Clay indexed the content by persons and places (persons are further distinguished by description and occupation), source and chart pedigree.