Much of the population of the south were Roman Catholic, French-speaking, or liberals who regarded King William I's rule as despotic. There were high levels of unemployment and industrial unrest among the working classes.
On 25 August 1830 riots erupted in Brussels and shops were looted. Theatergoers who had just watched La muette de Portici at the Monnaie theater house, joined the uproar and windows were smashed. Uprisings followed elsewhere in the country. Factories were occupied and machinery destroyed. Order was restored briefly after William committed troops to the Southern Provinces but rioting continued and leadership was seized by more radical elements, who started talking of secession.
A battle took place in Brussels. Cannons were fired in the Warande Park. Dutch troops were eventually forced to withdraw because of mass desertion of recruits from the Southern Provinces, while the States-General in Brussels voted in favour of secession and declared independence. In the aftermath, a National Congress was assembled and William refrained from future military action and appealed to the Great Powers. The resulting London Conference of major European powers recognized Belgian independence. Following the installation of Leopold I as "King of the Belgians" in 1831, King William made a belated military attempt to reconquer Belgium and restore his position through a military campaign. This Ten Days Campaign failed as a result of French military intervention. Not until 1839 did the Dutch accept the decision of the London conference and Belgian independence by signing the Treaty of London.