From Spalatro the line crosses the Adriatic to Fermo, and then following very closely the 43rd parallel of latitude, divides Italy into two nearly equal halves. The Gothic tribes settled to such an extent to the northward of this boundary as to influence the style of architecture in a very marked degree; while to the southward of it their presence can with difficulty be detected, except in a few exceptional cases, and for a very limited time.
Architecturally all the styles of art practised during the Middle Ages to the westward and northward of this boundary, may be correctly and graphically described as the Gothic style. All those to the eastward may with equal propriety be designated as the Byzantine style of art.
Anterior, however, to these, there existed a transitional style, properly called the Romanesque, which may be described as that modification of the classical Roman form, which was introduced between the reigns of Constantine and Justinian, and was avowedly an attempt to adapt classical forms to Christian purposes. To the eastward of the line of demarcation the transition was perfected under the reign of Justinian (a. d. 527 to 564), when it became properly entitled to the name of Byzantine. To the westward, in Italy and the south of France, the Romanesque continued to be practised till the 6th or 7th centuries; but about that time occurs an hiatus in the architectural history of Western Europe, owing to the troubles which arose on the dissolution of the Roman Empire and the irruption of the Barbarian hordes. When the art again reappeared, it was strongly tinctured by Barbarian influences, and may with propriety be designated the Gothic style, the essential characteristic being that it is the architecture of a people differing from the Romans or Italians in blood, and, it need hardly be added, differing from them in a like ratio in their architectural conceptions.
This nomenclature differs slightly from that usually employed in modern architectural works. This arises from the fact that the present names were introduced by persons writing monographs of the styles of their native countries, and not by any one who, taking a larger view of the subject, was attempting to classify all styles. It is of little consequence, for instance, to inquire why the Germans should call the architecture of such cathedrals as those of Spires, Worms, etc., by the absurd name of Byzantine, or to ask them what feature had been borrowed from the Eastern capital, or in what one particular they resembled the buildings of that division of Europe. They adopted a name, and so long as they did not extend their purview beyond the Rheinland, no harm was done. But with a general historian it is different; he has a definite use for the term, and he cannot admit within its limits any style or details which cannot establish their affinity to it.