was detached from Braine-l�Alleud and became part of Waterloo. In 1824, Waterloo grew again as the areas Roussart and Sainte-Gertrude from the Sonian Forest (Foret de Soignes) became part of the municipality too. Waterloo had 1571 inhabitants in 1801 and 3202 in 1846.
In 1795, the invaded territories were divided into 9 departments. Some municipalities, including Waterloo, became part of the Dyle department, which became the province of Brabant M�ridional in 1815 under the Dutch rule after the defeat of Napoleon. It changed name in 1830 when Belgium became independent and became the province of Brabant for 165 years.
In 1977, the second half of the hamlet of Chenois was detached from Braine-l�Alleud and became part of Waterloo together with a part of the hamlet next to the Lion.
In 1995, the province of Brabant was divided to match the limits of the regions created in 1980 (Wallonia, Brussels, Flanders). The part in which Waterloo is situated became the province of Walloon Brabant
