"a pidgin-speaking middle-of-the-forest indian chief"
You strike me as someone of a scientific bent - i.e. one who prefers clarity and careful defintions. Coming to this from a linguistics background, allow me to caution you re: use of the word "pidgin". Your notional "chief" lives in the "middle-of-the-forest". From this snipper I infer that his community is an isolated one, probably monolingual - i.e speaking the native tongue and no other. I therefore refer you to the Journal of Pidgin and Creole Langages:
pidginization – "The development into a pidgin." (C: 428) As a complex process of sociolinguistic change, it involves reduction of linguistic resources and restriction of use (Hymes). As a process of acquisition under restricted conditions, it involves the learning of a second language by speakers of different language of the dominant group (Bickerton). (R: 2) (Compare to creolization.)
pidginization hypothesis of second language learning – "Pidginization may be a universal first stage in second language acquisition, which results initially from cognitive constraints and then persists due to social and psychological ones," argues Schumann. This would explain why some second language learners end up using a simplified and restricted variety of the L2: "Schumann claims that Alberto's speech is pidginized as a result of his social and psychological distance from English speakers." (R: 219)
i.e. a pidgin emerges when a usually multi-lingual population needs to use a single, dominant tongue. Pidgins therefore developed in colonies of indentured slave workers where the slaves spoke many languages and drew of the language of the slavers (English, Dutch, French etc.) to construct an ad hoc, grammatically and lexically reduced lingua franca. However, children born into this situation mutually construct a richer version with full grammatical and lexical complexity. This is known as a creole language. The version of "English" spoke in Jamaica now is an example. A fully rich, complex and communicative language using English lexis but with quite different grammatical patterns.
I would content your notional, isolated chief speaks a rich language of equal complexity to English, very well developed to meet his communicative, pragmatic and semantic needs.