William I (1772–1843) was a Prince of Orange and the first King of the Netherlands and Grand Duke of Luxembourg. William implemented controversial language policies, founded many trade institutions and universities, and adopted a new constitution. However, the southern Netherlands became increasingly marginalized, and in 1830 the Belgian Revolution broke out. The war against the newly-declared Belgium caused considerable economic distress for the Netherlands, and in 1839 William signed the Treaty of London, which recognized Belgium. William abdicated the following year.Painting: Joseph Paelinck