Jadebusen
The predecessor of the Kaiserliche Werft was founded 1853 under an agreement of the Grand Duchy of Oldenburg and the Kingdom of Prussia. The object of this agreement was a protection of Oldenburg's merchant fleet by Prussian navy on the one hand, on the other to enlarge the Prussian sphere of influence in the western part of Germany. When the Jade Treaty was signed about 3.10 km² of Oldenburgian territory at the Jade Bight was ceded to Prussia.