The Fifth Coalition was an alliance between Austria and Britain formed in 1809 to fight Napoleon Bonaparte's French Empire.
Britain was already fighting France at sea and in alliance with rebels in Spain in the Peninsular War. Austria raised a fresh army to try to overturn the negative results of previous wars that had culminated in the Treaty of Pressburg. Although Austria won minor defensive victories, the absence of Russia or Prussia from the coalition meant that Austria was outnumbered and eventually defeated at the Battle of Wagram. Austria was compelled to sign the Treaty of Schönbrunn, losing yet more territory to Napoleon.
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