Oldenburg
a republic since 1918, formerly a Grand Duchy of North Germany, between lat. 52° 30′ and 53° 43' N., lon. 7° 35' and 8° 50' E., having N. having N. the North Sea, E. the territory of Bremen, S. and W. Hanover; area, 2,417 square miles. The surface is level, and so low on the coast as to render necessary the formation of dykes, as in Holland, to prevent inundations of the sea. The soil is rich on the banks of the rivers, but in other parts sandy or marshy. The principal rivers are the Weser, Hunte, Haase, Leda, and Jahde.
Of the lakes, Drummersee is the principal. The productions include flax, hemp, hops, rape seed, corn and potatoes.
Horses and cattle of superior breed, and sheep, are extensively reared. Its commerce is principally carried on in small vessels of to 40 tons, along the coast with Denmark, Holland, Hanover, etc. The duchy of Oldenburg was formed in 1773 by Joseph II., of the counties of Oldenburg and Delmenhorst.
It joined the Confederation of the Rhine in 1808, incorporated with the French empire by Napoleon I. in 1810, and was restored to the duke in 1814. Augustus first assumed the title of grand duke in 1829. Kniphausen was added to the grand-duchy in 1854. Oldenburg entered into an alliance with Hanover against Prussia in 1865, and after the defeat of the Austrians, submitted to Prussia, with which it signed a treaty of alliance in 1866. Capital, Oldenburg.
Pop. about 500,000.