Wagria (German: Wagrien, Waierland or Wagerland) is the northeastern part of Holstein in the German state of Schleswig-Holstein, corresponding roughly to the districts of Plön and Ostholstein. The word "Wagria" is derived from Germanic settlement of Waringer and just a bit later the West Slavic Lechites tribe of Wagri or Wagier, which meant "those who live by the bays". Wagria was occupied from Viking of Haithabu. It seems that the Wagrier are identical with the East Germanic tribe of Waringer (Latin Varini). This country is a historical landscape of Viking myths.
In the Middle Ages, and as still shown on old maps, Wagria was bordered on the north and east by the Baltic Sea from the Kiel Fjord to Lübeck Bay, and inland by the rivers Schwentine and Trave. Today, Wagria generally refers just to the Oldenburg Peninsula (Oldenburgische Halbinsel) in Ostholstein.
The highest elevation in the peninsula is the Bungsberg at 168 metres.
The Lechitic (Slavic) root of the name, Wagria, meant not only the so-called, present-day Wagrian peninsula, but the entire region between the Kiel Fjord, the middle reaches of the Trave, and the lower course of the river; a region with this name emerged at least as early as the 8th century. Wagria Castle occupied a central location in Oldenburg in Holstein (then called Starigard, or "Old Castle"); its ramparts still exist. Important settlements in Wagria were Oldenburg, Old-Lübeck (Liubice), and Plön (Plune).
In 1143, according to the vivid account by contemporary chronicler, Helmold of Bosau, Count Adolf II of Schauenburg and Holstein introduced German settlers, not only from his own territories of Holstein and Stormarn, but also from Westphalia and Holland, in order to develop the land of Wagria into a highly-profitable region as part of the German eastward expansion in the High Middle Ages:
The resident Slavs were thus also involved in this expansion or development.
- Arnold, Benjamin (1991). Princes and territories in medieval Germany, Cambridge University Press, Cambridge and New York, p. 156. ISBN 0-521-52148-3.
- Witt, Hermann (1982). 1000 Jahre Wagrien von Luitschaburg bis Lütjenburg. Sönksen Verlag Plön.