Having routed the Third Coalition raised against him at Austerlitz (1805), Napoleon was in characteristically uncompromising mood when a Fourth Coalition was raised against him in 1806. The volunteer cannon fodder on this occasion were Prussia, Russia, Saxony, Sweden and, in the background, Britain. Prussia bore the brunt, crushed at Jena, while a more circumspect Russia was nevertheless overwhelmed at Friedland, forcing Tsar Alexander to sue for peace. By the Treaty of Tilsit (1807), Prussia lost almost half its territory, Napoleon carving out a Kingdom of Westphalia for his brother Jerome, and a puppet Duchy of Warsaw. Napoleon forced Russia to vacate Wallachia, Moldova and the Ionian Islands it had captured from the Ottomans; he also demanded Russia’s support against his remaining enemies Sweden and Britain, and in the maintenance of the Continental Blockade. But Napoleon was insatiable, before the year ended, he was invading Portugal, igniting the Peninsular War.
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