Formed in 1806 from the Landgraviate of Hesse-Darmstadt as Napoleon restructured western Germany; renamed Grand Duchy of Hesse and by Rhine in 1816 to distinguish itself from the neighboring Electorate of Hesse (formed from Hesse-Kassel). Joined the German Confederation in 1815 and became a constituent grand duchy of the German Empire in 1871.
Monarchy abolished November 1918 in the German Revolution; Grand Duke Ernest Louis abdicated; became the People's State of Hesse.