The armed Belgian resistance movement effectively based itself in the wooded Ardennes region of the country. Elsewhere in Belgium it spent a great deal of its time gathering intelligence and passing it onto the British. By the end of 1941, ten resistance cells existed in Belgium and by the end of 1942, they operated 25 clandestine transmitters. By the time of D-Day in 1944, the number of transmitters had gone up to 40. British records from 1942 show that 80% of the intelligence gathered by all resistance movements in all occupied countries in that year came from Belgium. In particular, the reports sent through on the placing of German radar was vital to the Allies bombing campaign.
A secret printing press
However, there was one weakness in the set-up of the Belgian resistance that SOE (Special Operations Executive) had warned them off. The transmitters which sent so much vital intelligence data to Britain were also used to co-ordinate military ventures against the Germans - the destruction of bridges, rail lines etc. SOE recommended that the two should be split with some transmitters being used solely for intelligence transmissions and some being used solely for operational matters. This advice was never heeded and several of the resistance cells were caught as a result - and paid the price.
Alongside the 10 cells that spent their time sending intelligence to Britain, 12 armed units existed by the end of 1941. Ironically, there were probably too many of them in a country as small as Belgium and it increased the chance of them being compromised by the Gestapo. The largest of the groups was called the 'Legion Belge'. However, the Belgian government in exile based in London distrusted the long term motives of 'Legion Belge' as they believed that this movement did not want the exiled royal family back once the war had ended. This led to friction between the Belgian government in exile and SOE which wanted to encourage the work done by 'Legion Belge'.
A settlement between the Belgian government in exile and 'Legion Belge' was reached by July 1943 when it was given not only a constitution of its rights but also a specific set of instructions on what was expected of it. The 'Legion Belge' became the 'Armée Secrète' and its first task was to raise 50,000 people who would come under the command of the Allies when required.
The second most important resistance movement in Belgium was the 'Front de l'Indépendence'. This movement was given the task of co-ordinating civil resistance. However, all resistance movements in Belgium, however big or small, were concerned with civil resistance, intelligence gathering, sabotage and helping POW's to escape. All of them also had their own clandestine printing presses as well.
While all the resistance movements in Belgium sent valuable intelligence data to Britain, the movements themselves did not believe that they were getting their fair share of support from SOE. The main criticism was that SOE was not giving them enough supplies. While this may have been a fair criticism, it also failed to accept the fact that SOE had to deal with a great number of resistance movements in all of occupied Europe. All of them throughout occupied Europe probably felt that they needed more than SOE could supply if they were to be effective in what they did.
It is generally accepted that the most successful group in terms of material destruction was 'Groupe G' whose numbers never exceeded 3,000. On January 15th 1944, this group put out all high tension electric lines in Belgium simultaneously. Factories came to a standstill and it is estimated that this one action cost the Germans the equivalent of 10 million man hours of work.
By early 1944, the resistance movements were printing over 300 clandestine newspapers that circulated all over Belgium. In the previous year, they managed to publish 100,000 fake copies of 'Le Soir' - a newspaper controlled by the Germans. They were sold as real ones at news stands throughout the country.
One of the most important functions of the Belgian resistance was to assist the movement of escaped POW's and airman shot down during a raid. The most important escape line was called 'Comète' and it ran in close liaison with the Dutch and French resistance movements.