During the Battle of Belgium, the Belgian army was pushed back into a pocket in the northwest of Belgium and surrendered on 28 May.[5] The government fled to France, and later the United Kingdom, establishing an official government in exile under pre-war Prime Minister Hubert Pierlot.[6] They were responsible for forming a small military force made up of Belgian and colonial troops, known as the Free Belgian Forces and which fought as part the Allied forces.[7]