Sanders of the River by Edgar Wallace

There were occasions when Sanders came up against the outer world, when he learnt, with something like bewilderment, that beyond the farthermost forests, beyond the lazy, swelling, blue sea, there were men and women who lived in houses and carefully tabooed such subjects as violent death and such horrid happenings as were daily features of his life.

He had to treat with folk who, in the main, were illogical and who believed in spirits. When you deal in the abstract with government of races so influenced, a knowledge of constitutional law and economics is fairly valueless.