This thematic issue arose from a one-day symposium carrying the same title held at Manchester University on 21 May 2009. Papers by Paul Russell and Katrin Thier stem from the event, while those of Michael Benskin and David Parsons were later offered on invitation. 1 With such a vast theme, the four papers can offer just a sample of current research into the languages and the linguistic situation in Britain in the first millennium. Nonetheless, we believe the papers are representative of current research trends and together, with their varied yet interrelated themes, manage to cover considerable ground. The contributions focus especially on the linguistic impacts of the Roman and Anglo-Saxon invasions and settlements, though later contacts involving Irish and Old Norse also come up for discussion in the final paper. All papers therefore bear a resemblance, in that they each deal with issues relating to language contact and multilingualism in early Britain; however, the fields explored and the questions addressed by the authors differ considerably. The following topics are explored: the use of Latin in Roman Britain as viewed from the place-name evidence (Parsons), the influence of Latin on Brittonic morphology (Russell), Brittonic influence on verb-subject agreement in English dialects (Benksin), and how loanwords reflect the technological transfer at different periods (Thier).The first two papers, by Parsons and Russell, consider the linguistic impact of Latin in Britain during almost four centuries of Roman rule (ca. AD 43-410). As both authors make clear, opinions about the nature and use of Latin in Roman Britain have changed significantly in recent decades. Earlier suggestions that British Latin was more conservative in terms of its phonology than in other parts of the Empire have largely been discredited. Newly discovered inscriptions, in particular curse tablets in vernacular language, have added weight to this view, and it is now argued that British Latin shared several characteristics with the Latin of Gaul. Although Latin was undoubtedly spoken by many citizens in Roman Britain, some scholars have reasoned that Latin probably became the main vernacular language in the lowland areas of the South-East, which are known to have been intensely Romanised both archaeologically and culturally.Deducing the multilingual setting of late Roman Britain is complicated firstly by the fact that Latin was the only language committed to writing and, secondly, because of the rapidity of the Anglo-Saxon settlement from the mid-fifth century on, with its early epicenter in the South and East, which eradicated virtually all traces of the earlier linguistic situation. Substantial numbers Latin loanwords, including items of basic vocabulary, as attested in mediaeval Welsh, Cornish and Breton, are possibly suggestive of widespread Latin use in Roman Britain; more controversially, a not insubstantial number of early Latin loanwords in Old English could point in this direction too, but firm conclusions about language demographics ...