This book, Northern Lights, belongs to an epoch which is a generation later than that in which Pierre and His People moved. The conditions under which Pierre and Shon McGann lived practically ended with the advent of the railway. From that time forwards, with the rise of towns and cities accompanied by an amazing growth of emigration, the whole life lost much of that character of isolation and pathetic loneliness which marked the days of Pierre. When, in 1905, I visited the Far West again after many years, and saw the strange new life with its modern episode, energy, and push, and realised that even the characteristics which marked the period just before the advent, and just after the advent, of the railway were disappearing, I determined to write a series of stories which would catch the fleeting characteristics and hold something of the old life, so adventurous, vigorous, and individual, before it passed entirely and was forgotten. Therefore, from 1905 to 1909, I kept drawing upon all those experiences of others, from the true tales that had been told me, upon the reminiscences of Hudson's Bay trappers and hunters, for those incidents natural to the West which imagination could make true. Something of the old atmosphere had gone, and there was a stir and a murmur in all the West which broke that grim yet fascinating loneliness of the time of Pierre.Thus it is that Northern Lights is written in a wholly different style from that of Pierre and His People, though here and there, as for instance in A Lodge in the Wilderness, Once at Red Man's River, The Stroke of the Hour, Qu'appelle, and Marcile, the old note sounds, and something of the poignant mystery, solitude, and big primitive incident of the earlier stories appears.