Fortresses of the German Confederation

Under the term of the 1815 Peace of Paris, France was obliged to pay for the construction of a line of fortresses to protect the German Confederation against any future aggression by France. All fortresses were located outside Austria and Prussia — the two biggest, bickering powers of the Confederation.

Section of the on 3 November 1815, declared Mainz, Luxemburg, and Landau to be fortresses belonging to the Confederation of Germany, and stipulated that a fourth should be constructed on the Upper Rhine. In conformity with this act, a portion of the funds, which France was compelled to pay by way of indemnity for the cost of placing her on a peaceable footing, was thus appropriated: £200,000 were set aside for completing the works at Mainz; £800,000 were assigned to Prussia, to be applied upon its fortresses on the Lower Rhine; another £800,000 were reserved for constructing the new federal fortress on the Upper Rhine; and Bavaria was allowed £600,000 towards erecting another strong place on the Rhine, at Germersheim or some other point.

By 1835 the works about Mainz were completed; the twin fortresses of Koblenz and Ehrenbreitstein, and Cologne had been abundantly strengthened on the side of Prussia; and, on the Bavarian side, the fortress of Germersheim was in a state to defend the passage on the Upper Rhine. The western frontier of Germany had, in this way, been provided with a formidable line of defences against possible hostile actions by their neighbours. The eastern side of Germany has been additionally fortified by the erection of a strong citadel at Posen; and the southern was to be still further protected by the formidable works in course of construction at Brixen in the Tyrol.

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