Source of the Danube
As early as 1847 the following definition can already be found in the "Universallexikon des Großherzogtums Baden" (Universal Lexicon of the Grand Duchy of Baden): “Danube, the biggest river of Germany, rises at the Martinskapelle in a wild and lonely area of the Black Forest, is called Brege at its origin and forms the river Danube in Donaueschingen where it is unified with the Brigach." (German original: „Donau, der größte Fluß Deutschlands, entspringt bei der Martinskapelle in einer wilden und einsamen Gegend des Schwarzwaldes, heißt am Anfang Brege… und bildet erst in Donaueschingen, wo sie sich mit der Brigach vereinigt, die Donau.“)
Internationalization of the Danube River
On December 28, 1854, during the Crimean War (France, Britain, Sardinia, and Turkey versus the Russian Empire), the allies sent to Russia a note urging the internationalization of the river as one of the bases for a peace treaty:
. . . it would be desirable that the course of the Lower Danube . . . be withdrawn from the territorial jurisdiction. . . . In every case the free navigation of the Danube could not be secured if it be not placed under the control of a syndical authority, invested with the powers necessary to destroy the obstructions existing at the mouths of the river, or which may hereafter be formed there.