This appearance of a conquering Mongolian people in Europe may be taken to mark a new stage in human history. Until the last century or so before the Christian era, the Mongol and the Nordic peoples had not been in close touch. Far away in the frozen lands beyond the northern forests the Lapps, a Mongolian people, had drifted westward as far as Lapland, but they played no part in the main current of history. For thousands of years the western world carried on the dramatic interplay of the Aryan, Semitic and fundamental brunette peoples with very little interference (except for an Ethiopian invasion of Egypt or so) either from the black peoples to the south or from the Mongolian world in the far East.
It is probable that there were two chief causes for the new westward drift