Beginning with the connection between language and society and the history of social thought and linguistic theory, this chapter discusses the development of empirical work on variability in language use in social settings. It describes progress in sociolinguistics and how analysis of speech in relation to the social backgrounds of speakers in heterogeneous, stratified societies, e.g., their racial and ethnic affiliations, migration histories and power relations, relationships in multilingual settings, etc., rested on new methodologies and created new findings about linguistic diversity.

Guided by work on speech communities, sociolinguists found various patterns in the relation between language and society (including language change) by studying: ‘free variation’; language use in specific sociocultural settings (engendering ‘ethnography of communication’); language contact and pidgins/creoles; bi/multilingualism, language choice (engendering ‘sociology of language’) and code-switching; language use in diglossia (related to functional domains, social situation, interlocutor, subject matter, etc.).

Working with sociolinguistic variables, such as space, time, social class, ethnicity/race, sex/gender, and age, which constitute a complex object of multidimensional variability, the sociolinguist Labov found, e.g., that race/ethnicity and gender differences were more important than social class for language change in the USA.

Given these issues, the problem of identifying the linguistic system is complex and paramount.

Studies of social cohesion and childhood multilingualism in South Africa are important because of the confluence of social space and race in apartheid South Africa. A sociology of language approach is followed where the social spaces and structures in society are brought in relation to the multilingual repertoires of early childhood multilinguals. A main finding is that there is a paucity of research that describes the multilingual repertoires of early childhood multilinguals in South Africa; there is a need for longitudinal studies. Findings from adjacent fields indicate that there is widespread early childhood multilingualism in South Africa and that multilingualism is related to social cohesion in different ways. First, White South Africans see the addition of an African language to their repertoires as a way to foster social cohesion. Second, children of the developing Black middle class are exposed increasingly to spaces where populations are more integrated and where English is paramount. Finally, all studies reviewed in the chapter indicate a severe gap between the multilingual experiences of childhood multilinguals in South Africa and monolingual experiences in school where they are either taught in the home language or in English.