In 1746, however, he was forced to leave Brussels after it was besieged by French forces under Count Maurice de Saxe. He moved with the government of the Austrian Netherlands, first to Antwerp, then to Aachen. His request to be recalled from his difficult situation was heeded in June 1746. Two years later, he represented Maria Theresa at the Congress of Aachen at the close of the War of the Austrian Succession. Extremely displeased with the provisions that deprived Austria of the provinces of Silesia and Glatz and guaranteed them to the warlike King of Prussia, he reluctantly signed the resulting Treaty of Aix-la-Chapelle on 23 October 1748. Both fearing a nascent Prussia, the Austrian and French sides began to make overtures to each other.