Belgium is a European country that held great importance during World War II. In May 1940, Germany invaded Belgium, exiling the government, instituting new laws, and forcefully sending Belgian Jewish people into forced labor and concentration camps (US Holocaust Memorial Museum). During this time, the Belgian government created a government-in-exile in London. Later, in 1944, Allied troops came to Belgium and began to liberate the country from German forces. The Allied powers were able to re-capture Brussels, thus leading to the reinstatement of the Belgian government in the country (Wikipedia). By 1945, the country was reported to have been completely free of German occupation (Wikipedia).
Belgium is mentioned in The Remains of the Day when Stevens is in Dorset and meets the chauffeur who helps diagnose the car troubles that Stevens has. The chauffeur and his employer "had been in Belgium together when the Germans had invaded and they had been together again for the Allied landing" (Kazuo 111).