Duchy of Nassau

State · 1806–1865 CE · at its largest around 1809 CE

A duchy in western Germany centred on Wiesbaden, a member of the Confederation of the Rhine, which sided with Austria in 1866 and was annexed by Prussia.

On its lands while it lasted

• Düsseldorf (c. 1806 CE): Capital of Grand Duchy of Berg (1806–1813).
• Weilburg (c. 1806 CE): Capital of Duchy of Nassau (1806–1816).
• Wiesbaden (c. 1816 CE): Capital of Duchy of Nassau (1816–1865).

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