Once confined to the margins of discussion about linguistic variation and change in the history of American English, recent years have seen an explosion of work on language contact. We review and synthesise recent work and present original evidence on how contact has shaped many facets of American English across many regions, reaching from the lexicon and phonology through syntax and pragmatics. We draw especially on features less widely discussed until now and look at how these enrich our broader understanding of contact in American English. We pay special attention to the challenges of identifying features that do and do not come from language contact and begin to trace the paths by which features have found their way into American speech and writing. Ultimately, we argue that, in some sense, many distinct forms of American English have been and are being shaped by contact.

Neither New York City English (NYCE) nor Baltimore English (BE) have garnered much historical research, so there is little understanding of the origin and development of English in either region. In this chapter, we show that the settlement histories of NYC and Baltimore show that neither city fits Trudgill’s (2004) model of tabula rasa new dialect formation but suggest more complicated patterns of settlement and therefore English feature origins. For subsequent evolution, we discuss the impact of incoming migrants on the evolution of the dialects until the present day. As elsewhere in the United States, race and racialisation play prominent roles in separating out different co-territorial varieties and in stigmatisation and prestige. Besides historical analysis, we investigate these questions through archival materials, literary representations and lay observations. These sources, alongside later dialectological and variationist accounts, allow us to trace the origins of many features of the varieties. For instance, we find evidence that (i) r-lessness had emerged in NYCE by the end of the eighteenth century, (ii) a-prefixing occurred in NYCE until at least 1860, (iii) the wine–whine merger had begun in NYCE and BE by about 1840 and (iv) most features stereotypical of White working-class BE were in place by 1950.

The English language has been attested in Ireland since the late twelfth century but did not become widespread until the beginning of the seventeenth century when vigorous planting of English settlers took place. Distinct forms of Irish English began to develop which were a mixture of diverse dialectal inputs from England and transfer phenomena from Irish as the native population began to switch to the language of the colonisers. Almost as the same time as planting of English settlers started there was a movement out of Ireland, either by deportation or voluntary emigration, largely due to economic circumstances. This led to areas in overseas anglophone regions showing centres of Irish emigration, e.g. Appalachia with eighteenth-century Ulster Scots or the north-eastern coast of the USA with nineteenth-century southern Irish Catholics. At these locations the linguistic impact of Irish English was slight but traces can be found still which testify to this input.

The city dialect of Liverpool has a unique profile in the context of other urban varieties in Britain. It is well known for such features as stop lenition and the NURSE–SQUARE merger, along with TH-stopping, these traits in combination forming a set which is not replicated elsewhere. The present study examines the historical background to Liverpool English, its geographical position in relation to the counties of Cheshire to the south and Lancashire to the north. In addition, the role of immigration to the city, especially that of Irish people in the nineteenth century, is discussed and the role which this input may have played in determining the developmental course for Liverpool English is evaluated. Finally, the current position of local speech in the city is examined and possible future pathways are indicated.

The central idea of this chapter is koineisation, the process by which discrete varieties tend to form into a new compromise variety when speakers of these varieties find themelves living side by side. Dialect levelling and new dialect formation are central forces in the process. The case study considers what happens when closely related but discrete language varieties come together in new circumstances. Primary focus is given to contact between Scandinavian varieties and Low German in the late medieval and early modern periods and between Old English and Viking Norse in northern England in the early medieval period.