This article incorporates text from "The Political History of Poland" (1917) by Edward Henry Lewinski-Corwin, a publication now in the public domain. Owing to the frequent raids of the
Norsemen, the people of this region early organized an effective military force of defense. Under the protection of the military bands and their chiefs, the fields could safely be cultivated and the little, fortified towns (grody), which became places for the transaction of intertribal business and
barter, for common worship, and for the storage of goods during a foreign invasion could be successfully defended and the wrongs of the people redressed. The military bands and their leaders soon became the unifying force, and the
fortified towns, the centers of a larger political organization, with the freeman (Kmiec or Kmeton) as its base. The first historical town of this nature was that of Kruszwica, on the Lake of
Gopło. Kruszwica formed part of Poland since its establishment in the 10th century. {{multiple image of Kruszwica (ca.1160) is considered among the most precious
mediaeval manuscripts in Poland. Some historical writers attribute the change in the political organization of the primitive Polanie tribe to the influence of foreign commerce, which for geographic reasons had early centered on the Gopło. At that period the lake was a very large body of water with a level at least ten feet higher than at present. The many small lakes now existing in the region were in all probability a part of Gopło, and the valleys of the vicinity constituted the bottom of the lake. There are many reasons to believe that such was the
hydrography of the section in that remote age. In his description of Gopło, written five hundred years ago,
Jan Długosz, a Polish historian, speaks of a vast body of water, leading us to believe that the lake then was much larger than it is at the present time. There is reason to believe that five hundred years previous to this historian's time, before the primeval forests were cut, the lake was still larger. The supposition that Gopło at the time of its highest level was connected by means of small navigable streams with the rivers
Warta,
Oder and the
Vistula is quite plausible. The constructive fancy of the economic historian sees
flotillas of Pomeranian merchants moving to and from
Szczecin down the Oder and
Noteć. Here they met
merchants from the east, the southeast and the southwest of Europe. The Byzantine, Roman and Scandinavian cultures met at Kruszwica, the largest town on the banks of this vast internal sea of Poland, and exercised a revolutionary effect upon the modes of thought and the political institutions of the tribe. Otherwise the sudden transformation which took place from the tribal and communal organization of the people, which still existed in the second half of the eighth century, to the militaristic structure of society with a strong princely power, as is known to have existed in the ninth century, becomes almost unaccountable. The pressure from the west and north was, no doubt, an important element, but it alone would hardly seem sufficient to explain the change. Economic and cultural reasons had unquestionably exercised a great influence in the rapid molding of a new form of political life which was more adapted to conditions that had arisen since the change from nomadic pursuits to settled agriculture. Kruszwica was a county seat and
royal town of the
Kingdom of Poland, administratively located in the
Brześć Kujawski Voivodeship in the
Greater Poland Province. Following the joint German-Soviet
invasion of Poland, which started
World War II in September 1939, Kruszwica was
occupied by Germany until 1945. From 1940 to 1942, the German administration operated a
forced labour camp for
Jewish women in the town, and afterwards from 1942 to 1943 a forced labour camp for Jewish men. The
Polish resistance movement was active in Kruszwica. Władysław Kostuj, who organized the local branch of the
Secret Teaching Organization, was arrested in 1944 and murdered by the German gendarmerie. From 1975 to 1998, it was administratively located in the
Bydgoszcz Voivodeship. ==Demographics==