Kingdom of Prussia replaces Holy Roman Empire
1801–1815: Napoleonic Wars
The Treaty of Basel (1795) ended the War of the First Coalition against France. In it, the First French Republic and Prussia had stipulated that the latter would ensure the Holy Roman Empire's neutrality in all the latter's territories north of the demarcation line of the river Main, including the British continental dominions of the Electorate of Hanover and the Duchies of Bremen-Verden. To this end, Hanover (including Bremen-Verden) also had to provide troops for the so-called demarcation army maintaining this state of armed neutrality.
In the course of the War of the Second Coalition against France (1799–1802) Napoleon Bonaparte urged Prussia to occupy the continental British dominions. In 1801, twenty-four thousand Prussian soldiers invaded, surprising Hanover, which surrendered without a fight. In April 1801 the Prussian troops arrived in Bremen-Verden's capital Stade and stayed there until October of the same year. The United Kingdom of Great Britain and Ireland first ignored Prussia's hostility, but when it joined the pro-French coalition of armed "neutral" powers such as Denmark–Norway and Russia, Britain started to capture Prussian sea vessels. After the battle of Copenhagen the coalition fell apart and Prussia again withdrew its troops.
At Napoleon's instigation, Prussia recaptured British Hanover and Bremen-Verden in early 1806. On August 6 of the same year, the Holy Roman Empire was dissolved as a result of Napoleon's victories over Austria. The title of Kurfürst (Prince-elector) of Brandenburg became meaningless, and was dropped. Nonetheless, Frederick William III was now de jure as well as de facto sovereign of all of the Hohenzollern domains. Before this time, the Hohenzollern sovereign had held many titles and crowns, from Supreme Governor of the Protestant Churches (summus episcopus) to King, Elector, Grand Duke, Duke for the various regions and realms under his rule. After 1806 he was simply King of Prussia and summus episcopus.
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