Adolphe was Duke of Nassau from 20 August 1839 to 20 September 1866, when the Duchy was annexed to the Kingdom of Prussia.

In 1879, Adolphe's niece Emma of Waldeck and Pyrmont, the daughter of another of his half-sisters, married William III, King of the Netherlands and Grand Duke of Luxembourg.

In 1890, upon William's death without surviving male issue, their only daughter Wilhelmina succeeded to the Dutch throne, but was excluded from the succession to Luxembourg by Salic law.

The Grand Duchy, which had been linked to the Netherlands in personal union since 1815, passed to Adolphe in accordance with the Nassau Family Pact.

He mostly abstained from day-to-day governing; Prime Minister Paul Eyschen, in office since 1888, took care of the affairs of state.

This established a convention that the monarch would remain absent from the politics of the day, despite being vested with considerable reserve powers on paper.

Wisborg (also spelled Visborg) is the ruins of an old castle in the city of Visby within Oscar's former Dukedom of Gotland, but the title itself was created in the nobility of Luxembourg.

On April 20, 1842, the Adelsverein, Society for the Protection of German Immigrants in Texas, was organised in the Grand Duke's castle at Biebrich on the Rhine.