William III was King of the Netherlands and Grand Duke of Luxembourg from 1849 until his death in 1890. He was also the Duke of Limburg from 1849 until the abolition of the duchy in 1866.

The monarchy of the Netherlands is a constitutional monarchy whose role and position are governed by the Constitution of the Netherlands. Roughly a third of the Constitution explains the succession, mechanisms of accession and abdication to the throne, the roles and duties of the monarch, the formalities of communication between the States General of the Netherlands, and the monarch's role in creating laws.