The combinations of cultural, social, personal, and psychological factors, which are largely uncontrollable, are known to affect consumer behaviour. The marketer's task is to devote enormous efforts to understand how these factors interplay and ultimately, how they influence purchase behaviour.

Cultural Factors

Culture, that is, the way of life of a particular group of people, largely determines what people want and the way they behave. For instance, the Nigerian culture in Africa is distinct and different from the Italian culture in Europe and this influences product, pricing and media preferences.
One very important aspect of culture is a subculture. Subcultures represent specific elements of the broader culture and give members of a subculture a peculiar identity and basis for socialization.

Source: https://www.entrepreneurshipsecret.com/crucial-factors-affecting-consumer-behaviour/