Linguistic diversity -- multilingualism -- is, according to Mahapatra, found in most present-day nations (Mahapatra 1990: 1). In the Webster's Encyclopedic Unabridged Dictionary of the English Language (1996: 940), a multilingual person is defined as one "able to speak more than two languages with approximately equal facility". Kachru describes the same phenomenon as the "linguistic behavior of the members of a speech community which alternately uses two, three or more languages depending on the situation and function". (Kachru 1986a: 159).
According to Fasold (1984: 9), there are four different kinds of historical patterns that can lead to societal multilingualism. These patterns are migration, imperialism, federation and border area multilingualism. In this context, I will concentrate on the pattern of imperialism.
The subtypes of imperialism are colonization, annexation, and economic imperialism. Typical of imperialist processes is that relatively few people from the controlling nationality take up residence in the new area. Former British, French, Spanish, Portuguese and Dutch colonies in Africa, Asia and South America can serve as examples (ibid, 10).
Although relatively few people come to live in the subjugated territories, the language becomes very important in the territory (ibid, 10). Spolsky, too, remarks that the larger the scale of colonization from the homeland is, the more secure place the conquerors' language will be in the new land, although even a small ruling group may be able to maintain their language, provided they have contact with the homeland. Often in this case, the conquered people will be forced to learn the language of the conquerors (Spolsky 1978: 24).
In annexation and colonization, the imperialist language is likely to be used in government and education; in economic imperialism, the imperialist language is necessary for international commerce and finance: a foreign language will become widely used because of the economic advantage associated with it (Fasold 1984: 10).