In our rapidly urbanising world, cities have become important research sites for understanding language variation and change. Migration to cities brings people speaking different dialects and languages into close proximity with each other. Cities are thus fertile grounds for language contact, and this also accelerates language change across generations. These are the linguistic contexts that are studied in great empirical detail in Kerswill & Wiese's volume. The fifteen chapters are concerned with language contact and change in cities in northern Europe and sub-Saharan Africa. Pulling together research on what has been called ‘multiethnolects’ in Europe and ‘youth language practices’ in Africa, the book develops the concept of urban contact dialects. These can broadly be defined as ‘vernaculars that emerged in the context of migration-based linguistic diversity among locally born young people, marking their speakers as belonging to a multiethnic peer group’ (1). The main argument is that urban contact dialects develop differently depending on societal attitudes towards multilingualism.

Such attitudes towards multilingualism are captured in the book with the Bourdieuian term habitus. Societies in Africa seem to espouse a multilingual societal habitus, while a monolingual societal habitus seems to be dominant in European societies. In the introduction the editors explain that in societies with a multilingual habitus, which they roughly equate with sub-Saharan Africa and the Global South, codeswitching and extensive cross-borrowing between several languages are seen as normative and habitual, while in societies with a monolingual habitus, northern Europe and the Global North, language mixing practices are to some extent supressed and marginalised by strong monolingual national ideologies. These different habitus, the argument continues, shape the development of urban contact dialects over time. In societies with a multilingual habitus, urban speech develops much faster and in more complex ways, when compared to societies with a monolingual habitus. Thus, in the Global South, over time, urban contact dialects might become mutually unintelligible with standardised varieties of national or colonial languages. In contrast, in the Global North, urban contact dialects largely stay mutually intelligible with standardised varieties of national languages.

Kerswill & Wiese caution readers to understand these two habitus not as fixed rules of language change, but as ‘widespread dispositions’ that operate on a language ideological level and that can be navigated and contested by speakers in interaction.

It is also important to note that the two habitus do not neatly map on the distinction between Europe and Africa, or the Global North and Global South. The study on Tanzania (Uta Reuster-Jahn & Roland Kiessling), where a strong monolingual ideology persists, and the study on Finland (Heini Lehtonen & Heikki Paunonen), where multilingualism and extensive cross-borrowing is normative, are cases that challenge the simple idea that Europe is monolingual and Africa is multilingual.

Using spoken and written corpora, the chapters show in impressive empirical detail how urban contact dialects develop in relation to these two different types of linguistic habitus. In the first seven chapters, readers learn about the development of urban contact dialects (often named ‘youth languages’) in societies with a multilingual habitus, mainly in urban Africa. Kiessling's work on Camfranglais spoken in Douala and Yaoundé in Cameroon shows how language contact between Cameroonian Pidgin English and French has led to unique hybridisation processes in the phonology, prosody, semantics, syntax, and pragmatics of speech of young urban Cameroonians. This allows them to transcend ethnicities and renegotiate colonial and postcolonial language ideologies. Dorothy Pokua Ayepong & Nana Aba Appiah Amfo investigate what they call Ghanaian Student Pidgin English (GSPE), a dialect used by schoolchildren and university students. This dialect is based on West African Pidgin English but borrows features from Akan and Ga. GSPE has now expanded in usage and entered semiformal domains such as the church, the market, and social media.

Nico Nassenstein studies Lingala ya Bayankee or simply Yanké, a youth language practice that developed among street children and gangs in Kinshasa in the Democratic Republic of Congo. Today, Yanké can be considered a stylect that also includes particular ways of dressing and embodiments and that can be used variably by younger speakers who align with street culture. Maarten Mous & Sandra Barasa compare Sheng and Engsh in Kenya, two competing youth language practices that speakers can draw on to voice different personas. Engsh borrows from Sheng vocabulary but mainly retains Kenyan Standard English syntax. While Sheng is historically associated with impoverished neighbourhoods in east Nairobi and with criminality, street affiliation, and masculine toughness, Engsh is a more recent youth language practice that indexes modern Kenyan urbanity, education, and poshness. Ellen Hurst-Harosh's chapter studies three South African youth language practices, Tsotsitaal, urban varieties of isiXhosa and multilingual Sowetan isiZulu. The chapter provides comparative insights into the linguistic structures and social indexicalities of these urban contact dialects.

While all chapters situate urban contact dialects in their historical contexts, two chapter explicitly focus on diachrony. Fiona McLaughlin's study on Senegal compares late nineteenth-century Urban Wolof in Saint-Louis with early twenty-first-century Urban Wolof in Dakar. In both cases, borrowings from French into Wolof are attested but to different degrees and on different levels of linguistic description. For example, verbal borrowings from French have today greatly expanded, but phonological borrowings seem to have decreased. Lehtonen & Paunonen describe Old Helsinki slang in Finland, a contact dialect that emerged in the nineteenth century among migrant workers in Helsinki and that mixes Swedish, Finnish, and Russian lexis and phonology. Today, Old Helsinki slang has become a ‘Kulturgut’ used in magazines, advertisements, and rap songs as a discursive way of ‘honouring one's affiliation to local Helsinki culture’ (139). In the overall architecture of the book, the inclusion of this chapter in the first section reminds us that the multilingual and monolingual societal habitus do not neatly map onto the categorisations Global South and Global North (at least not when these terms are meant to designate simple Euclidian geographies, as further discussed below).

The eight chapters in the second part, focusing on countries with a monolingual habitus, turn their analytical attention on the fuzziness between the multiethnolects and the standardised national varieties. Reuster-Jahn & Kiessling describe the emergence of Lugha ya Mitaani (the language of the street) in Dar es Salaam, which is mutually intelligible with standard Kiswahili due to a strong monolingual societal habitus in Tanzania. Lugha ya Mitaani speech styles include semantic and pragmatic manipulations of Kiswahili and English lexicon and heavy use of metaphors for the purposes of creating humour. The chapter also provides a very useful comparison between Lugha ya Mitaani in Tanzania and Sheng in Kenya. Françoise Gadet's study of Greater Paris inquires how youth vernaculars emerge amidst the strong linguistic standardisation trends of France. Contact-induced change seems to happen largely at the level of lexical borrowings from Maghrebian Arabic and global English, while features on the level of phonology and grammar are largely similar to français populaire, a traditional urban vernacular associated mainly with young speakers from Paris.

Johan Gross & Sally Boyd trace the emergence of suburban Swedish in Gothenburg, Stockholm, and Malmö. Due to housing policies and historical layers of migration, immigrant communities from places such as Morocco, Turkey, Syria, Iraq, Somalia, and the Balkans usually live in the suburbs of the big cities. The spatial segregation of these multiethnic communities has led to the development of lexical innovations, morphosyntactic inversions, and phonological variation. Frans Hinskens, Khalid Mourigh, & Pieter Muysken study urban contact dialects in the Netherlands, commonly called straattaal ‘street language’, which are based on colloquial Dutch but influenced by contact with speakers with family backgrounds in Suriname, Indonesia, Turkey, Morocco, and China. Features of straattaal include phonological innovations, morpho-syntactical variation, and occasional code-switching. Pia Quist analyses urban contact dialects in Danish cities and finds variation, such as staccato rhythm, syntactical inversions, and lexical borrowings from Turkish and Arabic. Quist argues that there exists high variability among speakers and speech situations, and urban contact dialects in Denmark should thus be regarded as stylistic resources available for speakers to index social personae rather than fixed codes. Similarly, Bente A. Svendsen's study on contemporary urban speech styles in Norway discusses syntactical inversions, simplifications of grammatical gender, and lexical borrowings, but also highlights that variability of usage and style shifting are commonplace and allow speakers to perform identities in interaction. Like many authors in this section, Svendsen also points out that rap musicians have contributed to the expansion of urban contact dialects.

In the final two chapters, we read about the two editors’ own research on language change and dialect contact in Europe. Kerswill's chapter presents Multicultural London English (MLE), an emergent inner-city working-class urban contact dialect with influences mainly from Cockney and Jamaican Creole. Characteristic of MLE are phonological features such as H-dropping, K-backing, DH-stopping, and certain vowel shifts. Discourse features include the use of ‘innit’ as an invariable tag question and ‘man’ used as a pronoun. Yazgül Şimşek & Wiese analyse Kiezdeutsch, a contact dialect spoken in the working-class neighbourhoods of Berlin and associated with multicultural speakers who draw from local vernaculars, Turkish, Arabic, Kurdish, Russian, and (African varieties of) English and French. Structural features include variation in the use of articles, lexical borrowings, and phonological substitutions. Like MLE, Kiezdeutsch has expanded into various domains, such as social media and rap music.

The four commentaries provide critical discussions of key themes that surface across the chapters. Joseph Salmons emphasises the richness and complexity of urban contact dialects. This challenges the idea that contact dialects, like creole languages, are somewhat simplified versions of standard languages. He argues that ‘It's not so much that the traditional focus on simplification is wrong as it is that the topic fades away when we look at the full richness and the dynamism of these settings’ (163). While the chapters of this volume seem to corroborate such a perspective, Rajend Mesthrie's commentary also warns us that ‘the field of pidgin and creole linguistics should not be misused in trying to characterise urban varieties’ (339). This is so because creoles and urban contact dialects emerge in very different linguistic contact situations, particularly in terms of speakers’ access to standardised varieties. Yet, like Salmons, Mesthrie urges us to fathom the complexities of contact dialects in Europe and Africa. This would allow us to understand the linguistic effects of migration and trace how urban contact dialects become mainstreamed over time with increased mediatisation. David Britain asks important ontological questions about what we mean by ‘lects’ in the first place. He further asks where and when multiethnolects come into existence. These questions are situated within a very helpful critical discussion about our own citational practices as sociolinguists. Who we cite in our work is also discussed in Miriam Meyerhoff's commentary titled ‘Baby steps in decolonising linguistics’. She suggests that a ‘decolonising of contact linguistics involves not only opening the academy to more voices and more world views, but also not losing the precious gains we have made in the empirical and systematic study of the history and structure of language’ (154). The chapters in the volume do just this. They use established sociolinguistic methods to provide us with empirical and systematic insights into the history and structure of unique and creative linguistic practices that have typically emerged among marginalised young multicultural men living in big cities, both in Africa and in Europe.

So, aren't all settings described in these chapters situated in the Global South? In my mind, the children of migrants in suburban Sweden or the multicultural youth in London belong to the global southern majority, as much as the street children in Kinshasa or the criminalised gangs in Nairobi do. Such a conceptualisation requires us to contest the idea that the terms Global South and Global North innocently stand in for Euclidian (i.e. fixed) geographies divided by the equator or the Mediterranean. According to leading theorists in the field of decoloniality and southern theory, like Santos, the Global South must be understood ‘not as a geographical concept’, but as a ‘metaphor for the human suffering caused by capitalism and colonialism on the global level’ (Santos Reference Santos2016:18). The Global South ‘also exists in the geographic North (Europe and North America), in the form of excluded, silenced and marginalised populations’ (Santos Reference Santos2016:19). Pennycook & Makoni similarly suggest that ‘the idea of the Global South may be applied to the urban poor in cities in the northern hemisphere rather than to wealthy elites in the southern hemisphere’ (Pennycook & Makoni Reference Pennycook and Makoni2020:1–2).

While reading this book, I began to imagine the Global South as a metaphor that represents the rich multilingual labour and the linguistic creativity of racialised and marginalised populations living in cities across the world, who bring into contact various linguistic resources to make powerful claims about their identities. The Global North, then, metaphorically represents the suppression of such voices through monolingual ideologies perpetuated by the nation-state and its institutions. The Global North might also represent the capitalist exploitation of urban contact dialects in the form of mainstream mediatisations and resultant cultural appropriations by dominant groups. Could we understand the subtitle Insights from the Global North and South in such a metaphorical way, rather than simply thinking of two geographies? I leave it up to readers of this volume if they would agree with me that a metaphorical reconceptualisation of the Global South and Global North could help complexify dialectology's inherited understanding of language as being fixed in space and perhaps also initiate the next baby step in the decolonisation of sociolinguistics. It remains my hope that in the wake of such decolonial efforts, sociolinguistics can reckon with its own colonial heritage and thereby also address structural inequalities that exist in our discipline, such as the dominance of English or the fact that many European researchers go and study languages in Africa, while it is uncommon for African researchers to conduct research on European languages.