The western linguistic boundary of Poland extends through the German provinces of Silesia and Posen. Here a gradual replacement of the language by German since the sixteenth century is noticeable. At that time the Oder constituted the dividing line, south of the point of the confluence of the Nissa between Brieg and Oppeln. As late as 1790 the population of Breslau was largely Polish. Today over 75 per cent of the inhabitants of the city and the neighboring towns and villages are Germans. The district north and south constitutes in fact an area of linguistic reclamation.
The westernmost extension of Polish occurs in Posen, at the base of the provincial projection into Brandenburg. Around Bomst the percentage of Polish inhabitants is as high as 75 per cent. The line extends northwards to Birnbaum, after which it assumes a northeasterly direction. In spite of this occidental reach, however, the area of Polish speech within German boundaries is broken in numerous places by German enclaves of varying size.[105]
In western Prussia, the Poles form compact inclusions in the German mass and attain the Baltic shores, where they occupy the entire western coast of the Gulf of Danzig. From Oliva and Danzig the line extends to Dirschau (Tezew) and crosses the Vistula about six miles below the city. It then strikes east and turns southwards towards Marienwerder (Kwidzyn) and Graudenz. Proceeding due east from here, the boundary passes south of Eylau, the southern territory of the Masurian lakes, and on into Russian territory, until Suwalki is reached. The eastern frontier begins at this point and is prolonged southwards, according to Slav authorities, through Augustow, Bielostok,[106] Surash, Bielsk, Sarnaki, Krsanostaw and Tomaschow.
The advance of the area of Polish speech, in the form of a tongue of land, to the Baltic coast, is a proof of intimate dependence between Polish nationality and the basin of the Vistula. This northernmost section of the territory in which Polish is spoken, lies entirely within Prussian territory. Centuries of Teutonic influence failed, however, to eradicate completely Slavic language or customs in the valley of the great river. Between Thorn and Danzig, on the left bank of the Vistula, it is estimated that 650,000 Poles are scattered. On the right, the Prussian districts of Lobau, Strassburg and Briesen are centers of intense Polish life and culture. The city of Danzig itself, with a Polish element of only 10 per cent, still gives strong evidence of its Polish institutions. Its monuments are memorials of Poland’s history, and many of its families bear Polish names even though their members use German as a vernacular.
Originally a free town, Danzig owes its predominant German population to the inflow of traders of this nationality who have swarmed within its walls since the sixteenth century. The city, standing like a sentinel at the mouth of the Vistula, is in every sense a creation of the river. Traffic from Poland’s innermost districts flows towards the country’s great waterway to be finally landed on the wharves of Danzig. Prior to the partition of Poland, the city was nominally a dependency of that country, but its inhabitants had been granted special trading privileges as well as the right of governing themselves. The city’s commercial relations were highly favored by such a régime and business men from the surrounding country were not slow to realize the exceptional advantages which settlement in the city afforded. By the end of the seventeenth century its population consisted largely of German merchants and their dependents. Frederick II with characteristic far-sightedness realized the extent to which this seaport, together with the river city of Thorn, controlled the traffic between Brandenburg and old Prussia. He did not succeed however in annexing the two cities to his dominions, for it is only since 1815 that they have formed part of Prussian territory.
The American Geographical Society of New York
Frontiers of Language and Nationality in Europe, 1917, Pl. IV
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