The War of the Fifth Coalition was fought in 1809 by a coalition of the Austrian Empire and the United Kingdom against Napoleon's French Empire and Bavaria. Major engagements between France and Austria, the main participants, unfolded over much of Central Europe from April to July, with very high casualty rates for both sides. Britain, already involved on the European continent in the ongoing Peninsular War, sent another expedition, the Walcheren Campaign, to the Netherlands in order to relieve the Austrians, although this effort had little impact on the outcome of the conflict. After much campaigning in Bavaria and across the Danube valley, the war ended favourably for the French after the bloody struggle at Wagram in early July.
The resulting Treaty of Schönbrunn was the harshest that France had imposed on Austria in recent memory. Metternich and Archduke Charles had the preservation of the Habsburg Empire as their fundamental goal, and to this end the former succeeded in making Napoleon seek more modest goals in return for promises of Franco-Austrian peace and friendship. Nevertheless, while most of the hereditary lands remained part of Habsburg territories, France received Carinthia, Carniola, and the Adriatic ports, while Galicia was given to the Poles and the Salzburg area of the Tyrol went to the Bavarians. Austria lost over three million subjects, about one-fifth of her total population, as a result of these territorial changes.