Helmold of Bosau

Helmold of Bosau (ca. 1120 – after 1177) was a Saxon historian of the 12th century and a priest at Bosau near Plön. He was a friend of the two bishops of Oldenburg in Holstein, Vicelinus (died 1154) and Gerold (died 1163), who did much to Christianize the Polabian Slavs.

Helmold was born near Goslar. He grew up in Holstein, and received his instruction in Brunswick from Gerold, the future bishop of Oldenburg (1139–42). Later he came under the direction of Vicelinus, the Apostle of the Wends, first in the Augustinian monastery of Faldera, afterwards known as Neumünster (1147–53). He became a deacon about 1150, and finally became a parish priest in 1156 at Bosau on Großer Plöner See.

At Bishop Gerold's instigation Helmold wrote his Chronica Slavorum, a history of the conquest and conversion of the Polabian Slavs from the time of Charlemagne (about 800) to 1171. The purpose of this chronicle was to demonstrate how Christianity and the German nationality gradually succeeded in gaining a footing among the Wends, especially in the eastern portion of Holstein. As an eyewitness he gives a clear description in fluent Latin of Vicelinus's missionary labors, of the founding of the bishopric in Oldenburg, of the transfer of this bishopric to Lübeck when German commerce at the latter place had become more important than in the former city, of the spread of German influence among the Wends, of the merciless subjugation and extermination of these, and of the summoning to their lands of foreign settlers, principally Westphalian and Dutch. The work is divided into two parts: the first covers a period closing with the year 1168, while the second continues to the year 1171. This second part, however, was written subsequently to 1172.

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