The German Mediatisation is the name of the process of secularisation and mediatisation which occured in Germany during and after the Napoleonic Wars. "Secularisation" is the process of removing temporal authority from spiritual leaders, such as Bishops, Abbots, and Abbesses. "Mediatisation" is the process of annexing one states' territory but leaving the annexed states' rulers with specific rights and priveleges. The secularisation of the states in Germany was complete in 1803. The mediatisation occured from 1806 - 1815. The states mediatised before the formation of the Confederation of the Rhine (July 12 1806), or those ruled by states which did not have a seat in the College of Princes or one of the four Benches of Counts, are not considered amongst the "Mediatised Houses".
In 1797 Napoleon Bonaparte defeated the combined forces of the Holy Roman Empire, and by the Treaty of Campo Formio (1801) annexed all lands west of the Rhine River. It was the responsibility of the Holy Roman Emperor to compensate many now stateless nobles with new lands, and the only lands to give were those held by ecclesiastical states. With France's insistence, the Reichstag in 1803 officially secularised all of the ecclesiastical states and redistributed their lands amongst the nobles of Germany.
In 1806 the Holy Roman Empire was abolished, and Napoleon Bonaparte had created the Confederation of the Rhine in its stead. As an incentive to join the confederation, states which joined were granted permission to mediatise neighbouring states. Further mediatisations occured in 1807 with the creation of the Kingdom of Westphalia, when Napoleon annexed northwestern Germany to enforce the Continental Blockade in 1810, and futher mediatisations took place at the Congress of Vienna in 1814/5. Those houses which were mediatised became known as the "Mediatised Houses".
Compare the list of Mediatised States with the Mediatised Houses.
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Bremen, 
Hamburg, 
Lübeck, 
Augsburg, 
Nuremberg and 
Frankfurt. Of these, Augsburg was mediatised to Bavaria in 1805, Nuremberg in 1806, Frankfurt to the Prince-Primacy in 1806, and Bremen, Hamburg and Lübeck to France in 1810. Frankfurt, Bremen, Hamburg and Lübeck were later restored at the Congress of Vienna.
