Rhine crisis

The Rhine crisis of 1840 was a diplomatic crisis between the Kingdom of France and the German Confederation, caused by the insistence of French minister Adolphe Thiers that the river Rhine be reinstated as France's border in the east, at a loss of some 32.000 km² of German (mostly Prussian) territory.

The territories of the Left Bank of the Rhine, which French troops had conquered in 1795, had been returned to German (mostly Prussian) control after the 1815 Congress of Vienna, forming the Rhine Province. After a diplomatic defeat in the Oriental Crisis of 1840 France shifted its focus to the Rhine, and the French government, led by Adolphe Thiers, restated its claim to the areas on the left bank, to re-establish the Rhine as a natural border. These claims reinforced ressentiment among the Germans against the French, and increased nationalism on both sides. New nationalist songs were written in France and Germany and achieved huge popularity, most famously the German songs "Die Wacht am Rhein", "Der Deutsche Rhein" and the "Lied der Deutschen", the national anthem of Germany since 1922.

In the end the crisis passed without war breaking out, though it again established the importance of the Rhine in European culture and politics.

The Greek War of Independence and the Russo-Turkish War (1828–29) had considerably weakened the Ottoman Empire, and after Sultan Mahmud II refused to acknowledge Muhammad Ali Pasha (viceroy of the Ottoman territory Egypt) as the Stadtholder of Syria, Egyptian troops moved into Palestine and Syria, reaching Anatolia by 1832.

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