Roman Britain and the English Settlements

Roman Britain and the English Settlements is a book by R.G. Collingwood and J.N.L. Myres. In his Preface (dated 14 January 1936), Collingwood thanks his "colleague Professor J.R.R. Tolkien" for having helped him "untiringly with problems of Celtic philology" (p. vii). Tolkien is again explicitly mentioned in a footnote: