The national council of the 17 provinces of the Netherlands, the Estates-General met in Brussels beginning in 1548-1549. The body dealt with issues of concern common to all the Estates of the provinces. Measures it took included determining when currency should be coined and fixing its value. The southern provinces continued to meet in the Estates-General following the independence of the Netherlands (1648). It was abolished during the French regime.
The States-General was the parliamentary governing body under the Dutch regime, when it met both in The Hague and in Brussels at the Palais de la Nation.
Historical Dictionary of Brussels. Paul F. State.