Nordic theory, in Grant's formulation, was similar to many 19th-century racial philosophies which divided the human species into primarily three distinct races: Caucasoids (based in Europe, North Africa and Western Asia), Negroids (based in sub-Saharan Africa), and Mongoloids (based in Eastern and Central Asia). Nordic theory, however, further subdivided Caucasoids into three groups: Nordics (who primarily inhabited most of Northern Europe aside from Wales and parts of Ireland, England and Scotland), Alpines (whose territory included central and eastern Europe and parts of Asia), and Mediterraneans (who inhabited most of southern Europe, parts of the British Isles, North Africa, and the Middle East).
In Grant's view, Nordics probably evolved in a climate which "must have been such as to impose a rigid elimination of defectives through the agency of hard winters and the necessity of industry and foresight in providing the year's food, clothing, and shelter during the short summer. Such demands on energy, if long continued, would produce a strong, virile, and self-contained race which would inevitably overwhelm in battle nations whose weaker elements had not been purged by the conditions of an equally severe environment". The "Proto-Nordic" human, Grant reasoned, probably evolved in eastern Germany, Poland, and Russia, before migrating northward to Scandinavia.
The Nordic, in his theory, was "Homo europaeus, the white man par excellence. It is everywhere characterized by certain unique specializations, namely, wavy brown or blond hair and blue, gray or light brown eyes, fair skin, high, narrow and straight nose, which are associated with great stature, and a long skull, as well as with abundant head and body hair". Grant categorized the Alpines as being the lowest of the three European races, with the Nordics as the pinnacle of civilization.
The Nordics are, all over the world, a race of soldiers, sailors, adventurers, and explorers, but above all, of rulers, organizers, and aristocrats in sharp contrast to the essentially peasant character of the Alpines. Chivalry and knighthood, and their still surviving but greatly impaired counterparts, are peculiarly Nordic traits, and feudalism, class distinctions, and race pride among Europeans are traceable for the most part to the north.
Grant while aware of the "Nordic Migration Theory" into the Mediterranean appears to reject this theory as an explanation for the high civilization features of the Greco-Roman world.
The mental characteristics of the Mediterranean race are well known, and this race, while inferior in bodily stamina to both the Nordic and the Alpine, is probably the superior of both, certainly of the Alpines, in intellectual attainments. In the field of art its superiority to both the other European races is unquestioned.
Grant also considered North Africa as part of Mediterranean Europe:
Africa north of the Sahara, from a zoological point of view, is now, and has been since early Tertiary times, a part of Europe. This is true both of animals and of the races of man. The Berbers of north Africa to-day are racially identical with the Spaniards and south Italians.
Yet, while Grant allowed Mediterraneans to have abilities in art, as quoted above, later in the text he remarked that true Mediterranean achievements were only through admixture with Nordics:
This is the race that gave the world the great civilizations of Egypt, of Crete, of Phoenicia including Carthage, of Etruria and of Mycenaean Greece. It gave us, when mixed and invigorated with Nordic elements, the most splendid of all civilizations, that of ancient Hellas, and the most enduring of political organizations, the Roman State. To what extent the Mediterranean race entered into the blood and civilization of Rome, it is now difficult to say, but the traditions of the Eternal City, its love of organization, of law and military efficiency, as well as the Roman ideals of family life, loyalty, and truth, point clearly to a Nordic rather than to a Mediterranean origin.
According to Grant, Nordics were in a dire state in the modern world, where due to their abandonment of cultural values rooted in religious or superstitious proto-racialism, they were close to committing "race suicide" by being miscegenated with and out-bred by more inferior stock who were taking advantage of the transition.
