What is the importance of multiculturalism to the theme of White Teeth?

It is impossible to ignore the way in which Smith is presenting a picture of London that is multicultural to its very core. The one major English character marries a lapsed Jamaican Jehova's Witness and has a best friend who is an immigrant from Bangladesh. Throughout, Smith introduces themes such as immigration and the clash of different cultures in the arena of London, UK. Note, for example, the following quote that draws attention to the reality of life for immigrants in the UK:

These days, it feels to me like you make a devil's pact when you walk into this country. You hand over your passport at the check-in, you get stamped, you want to make a little money, get yourself started... but you mean to go back! Who would want to stay? Cold, wet, miserable; terrible food, dreadful newspapers--who would want to stay? In a place where you are never welcomed, only tolerated. Just tolerated. Like you are an animal finally house-trained.

Smith is definitely challenging the status quo in this novel by offering such views and trying to suggest to her English speaking audience that immigration is becoming far more of a fact of modern-day life than perhaps the reader would care to admit. Multiculturalism is therefore presented in this novel through the tremendous variety in all of the characters and how they come from numerous religions, countries and different locations and are all crammed together in London in one glorious mish-mash of culture and background. It is the interplay of these cultures, and how, more seriously, characters try to deal with their migration and the kind of issues raised in the quote above, that make this novel multicultural.

How does multiculturalism impact British characters and society in White Teeth?

Multiculturalism is shown as a dominant factor in British society as it affects the characters in White Teeth, especially in the London neighborhood where much of the novel is set. Author Zadie Smith employs several generations of English people of diverse heritages to show the social transformations that occurred after World War II. While the novel's action primarily takes place as the twentieth century draws to a close, Smith's treatment addresses varied national and racial influences on British culture. As she focuses on characters who came to England from former parts of the British Empire, and on their descendants, she encourages the reader to ask what it means to be British.

Friendship is one significant component of multiculturalism as Smith presents it. The characters Archie and Samad are in the older generation, among whom an intercultural, interracial friendship might seem less likely. Marriage is another realm where multicultural dimensions strongly emerge, as Archie and Clara are an interracial couple, who come together despite national and age differences.

Along with the overall positive interactions among the three families, the harsher realities are suggested through the difficulties that lead Archie to try taking his life and that disillusion Samad with materialism as a corrupting influence on modern youth.

For the younger generation growing up in a changing social environment, Irie, Millat, and Joshua do more than anchor the personal situations of individuals. They are embody social ambitions and show how lived circumstances contradict common assumptions or override stereotypes.