French resistance during the Battle of Normandy
Following operations Dingson and Samwest (carried out from the night of 5-6 June 1944 by the commandos of the 4th Battalion of the French Special Air Service (SAS) and aiming to coordinate resistance actions in Brittany), the Germans gradually managed to destroy the French armed groups (in particular the one born thanks to Operation Samwest, destroyed on 12 June 1944) which converged towards the maquis of Saint-Marcel. A week after the beginning of these operations, the resistance fighters were scattered, hunted down and a good number of them could not join the maquis.
In order to maintain the continuity of the actions of resistance with the survivors of operation Samwest and in order to strengthen in number and means the forces of Saint-Marcel, the French SAS launched Operation Grog, commanded by Captain Deplante, on June 13, 1944. Air drops of arms and ammunition that were carried out until then on the bases of Samwest and Dingson, were carried out from this moment on the base installed by Grog. The collection of the elements is then carried out near Pontivy (under the responsibility of Captain Leblond until July 1944 which also took over the military training and equipment of new recruits joining the ranks of the Free French forces). Operation Grog held until the general insurrection in August 1944, after the breakthrough of Avranches carried out by the Americans.