The name Wagrien ( Waierland, Wager country Wagrien ( Slavic ): living on the bays ' ) denotes the northeastern part of Holstein in Schleswig -Holstein, which is roughly the districts of Plön and East Holstein.

Since the Middle Ages, and on old maps still seen Wagrien was limited by the Kiel Fjord to Lübeck Bay to the northeast of the Baltic Sea, inland through the rivers Schwentine and Travelodge. Today, usually only the Oldenburgische peninsula in East Holstein is called Wagrien.

The name Wagrien goes back to the Slavic tribe of the Wagrians, who lived not only today's Peninsula Wagrien, but since at least the 8th century the whole space between Kiel Fjord, the average Travelodge and the lower reaches of the river. The central Wagrians Castle was located in Oldenburg in Holstein (then Starigard =, old castle ' ), the Wall still exists. Important places of Wagrians were Oldenburg and Alt- Lübeck ( Liubice ) and Plön ( Plune ).

In 1143, led Count Adolf II ( Schauenburg and Holstein ) to the graphic account of the contemporary chroniclers Helmold of Bosau German settlers from its territories Holstein and Stormarn and from Westphalia and Holland brought about in order to develop the country Wagrien during the High Middle develop land profitably:

" Then broke a countless number of different tribes, took families and belongings with and came to Count Adolf after Wagrien to take the promised land in possession. And that first received the Holsten residences in the most protected area west Segeberg, on the Trave, in the plane Schwentine box and everything that extends from the Schwale to Grimmelsberg and Ploen Lake. The Darguner country colonized the Westphalia, which Eutiner the Dutch and Süsel the Frisians. Plön country but remained uninhabited. Oldenburg and Luetjenburg and other coastal areas he let colonize of the Slavs, and they became tributary to him. "

The local Slavs were so involved in this development of the land with.

The highest point of the peninsula is the Bungsberg with 168 m.