This work is an attempt—whether successful or not the critic must decide—to give a concise summary of the facts at present available for forming a theory as to the origin and development of Celtic art in Great Britain and Ireland. By Celtic art is meant the art of the peoples in Europe who spoke the Celtic language, but it must always be borne in mind that although linguistically they were Celts, yet racially they were of mixed Celtic and Iberian blood, so that their art was possibly quite as much Iberian as Celtic. It is only since the epoch-making discoveries of Schliemann in Greece, of Flinders Petrie in Egypt, and of Arthur Evans in Crete that it has been possible in a satisfactory manner to connect the culture of Britain in the Bronze Age with the corresponding culture on the Continent. It is now quite clear that certain characteristic decorative motives, such as the divergent spiral, are of foreign origin instead of having been invented in Ireland, as was at one time believed. Other discoveries made in England, more especially those at Aylesford, Glastonbury, Mount Caburn, and Hunsbury, have thrown an entirely new light on the archæology of this country by showing that the Early Iron Age began here two or three centuries at least before the Roman occupation. Lastly, the explorations made by Continental antiquaries at Hallstatt in Austria, La Tène in Switzerland, and in the Gaulish cemeteries of the Marne district in France, point to the sources of the culture to which the late Sir Wollaston Franks gave the name “Late-Celtic.”

Celtic art naturally divides itself into two distinct periods, the Pagan and the Christian. With regard to the latter, the remains have been so fully investigated that it is hardly probable any new facts will be brought to light which will seriously alter the conclusions now arrived at. With regard to the Pagan period the case is altogether different, as most of the finds hitherto made have been due to accident, and until the large number of inhabited and fortified sites belonging to this period are systematically excavated our knowledge must necessarily remain incomplete.

I have endeavoured to give in the footnotes all the sources whence my information has been obtained, but I should like more especially to acknowledge my indebtedness to A. Bertrand and S. Reinach’s Les Celtes dans les Vallées du Pô et du Danube; J. Anderson’s Scotland in Pagan Times and Scotland in Christian Times; Arthur Evans’ papers on the Aylesford, Æsica, and Limavady finds in the Archæologia; and George Coffey’s papers on the ornament of the Bronze Age, Newgrange, etc., in the Journal of the Royal Society of Antiquaries of Ireland, and in the Transactions and Proceedings of the Royal Irish Academy.

The theory of the evolution of Celtic knotwork out of plaitwork (as explained on pages 257 to 278) is entirely original, and, simple as it appears when explained, took me quite twenty years to think out whilst classifying the patterns that occur on the early Christian monuments of Scotland, England, Wales, and Ireland, nearly all of which I have examined personally.

No illustrations are given of the pages of the Celtic illuminated MSS. on account of the difficulty of making satisfactory reproductions of them on a small scale. I have thought it better to refer the reader either to the MSS. themselves or to the Publications of the Palæographical Society and Professor J. O. Westwood’s Miniatures of the Anglo-Saxon and Irish Manuscripts.

A large number of photographs of Late-Celtic metalwork in the British Museum have been specially taken for this work by Mr. H. Oldland, with the kind permission of Mr. C. H. Read, F.S.A. I am indebted to the Rev. Canon W. Bazeley for obtaining a photograph of the Birdlip mirror in the Gloucester Museum, and to Mr. George for the loan of Sir H. Dryden’s drawings of the Hunsbury sword-sheath in the Northampton Museum. Mr. George Coffey, M.R.I.A., of the Museum of the Royal Irish Academy, has also from time to time been good enough to assist me in various ways. The photographs of the cast of the Nigg cross were taken by Messrs. M. and T. Scott, of Edinburgh, for Mr. D. J. Vallance, the curator of the Museum of Science and Art at Edinburgh.

For the use of electrotypes of blocks I have to give my best thanks to the Society of Antiquaries of London,[1] the Society of Antiquaries of Scotland,[2] the Royal Society of Antiquaries of Ireland,[3] the Royal Irish Academy,[4] the Royal Archæological Institute,[5] the Cambrian Archæological Association,[6] the Somersetshire Archæological Society,[7] and the publishers of the Antiquary,[8] the Reliquary,[9] and the Illustrated Archæologist.[10] Plates XXVI., XXIX., XXXV., XXXVI., and XXXVII. are from the series of photographs taken by Mr. W. G. Moore, of Upper Sackville Street, Dublin, for the Royal Irish Academy.