(Operation “Jupiter île d’Oléron” from April 30 to May 1, 1945)
From April 30 to May 1, 1945, “Operation Jupiter” took place on the island of Oléron, a military action of maritime landing (3rd Landing of France), aimed at liberating from German occupation, one the last pockets of occupation after Royan and Le Verdon, liberated from April 18 to 20, 1945; but before La Rochelle and Ré, delivered on May 8, 1945; which still escapes the authority of General de GAULLE.
Installed on the island of Oléron since June 29, 1940, because of its strategic position which controls the estuary of the Gironde and the passes leading to the future submarine base of La Pallice, the Germans had all the leisure to organize their defences. From 1942, against an Anglo-American landing which, as in 1917, would approach the Atlantic coast in one of its ports, then from 1944 against a powerful enemy who would come from the continent. In a directive of August 17, 1944 from the Führer himself, Adolf HITLER urged his troops “to hold out until the end” inside the last bastions of the Atlantic.
For this the Organization Todt, in charge of the development of the “Atlantic wall”, has built on the edges of the island 32 stützpunkt (support points) and 42 campaign positions, some of which include pieces of artillery ranging from 75 to 155 mm. However, only 11 positions were completed in 1945. These works were supplemented on the beaches by concrete tetrahedrons, Cointet elements, Czech hedgehogs and “Rommel stakes”, intended to rip open any landing craft at high tide. . Without forgetting the minefields which constitute a second curtain of defense.
The German garrison which depends on the sector of La Rochelle (vizeadmiral Ernst SCHIRLITZ), has been commanded since January 1945 by the korvettenkapitän Alfred GRAF SCHILTZ VON GÖRTZ UND VON WRISBERG who has his PC avenue Bel-Air in Saint-Pierre d’Oléron. It has about 2,200 men, of which 1,380 come from the Kriegsmarine.
They mostly belong to the leichte Marine-Artillerie-Abteilung 687 (Light Coastal Artillery Group 687) commanded by korvettenkapitän Werner SCH-EFFER. This artillery group comprises 3 mobile intervention companies (i.e. 690 men, including 40 Russians, 50 Poles and 25 Austrians) based respectively in Dolus, Saint-Pierre and Saint-Georges; and 3 artillery batteries (370 men). The batteries comprise for one, 16 horse-drawn 75 mm cannons and 6 Schneider 155 mm howitzers, for the other, the leichte schützen-kompanie (light support company), 7 anti-aircraft guns of 25 mm and 11 mortars of 81 mm, and finally for the last, an anti-tank company equipped with 12 PAK from 37 to 50 mm. 320 men depend on the Marine-Flakiculaire-Abteilung 812 (Naval group of anti-aircraft artillery 812) or MaFla 812, belonging to the Marine-Flak-Brigade V (whose PC is in Saint-Nazaire), created in March 1942 between the islands of Ré and Oléron, composed for its part, of 3 batteries (including 2 of 75 mm Flak M 35 Vickers) and a half company of 6 Siemens projectors of 150 cm. The whole is under the orders of Oberleutnant KRÖNER. Finally, the soldiers of the 2 Komp / 3 Funk-Mess-Abteilung (2nd company of the 3rd radio surveillance battalion) serve the radar and optical transmission installations at Pointe de Chassiron.
350 men depend on the Wehrmacht and serve either in the Heeres Kotier Artillerie Abteilung 1280 (Coastal Artillery Group of the Army 1280) of the hauptmann MÜLLER. Since October 1944, it has replaced Major SORG’s HAA 1180 (left to reinforce the La Rochelle sector) and has 4 firing batteries (230 men). The others are attached either to the 6th fortress infantry company of the 80th Corps (6/Festa LXXX) of hauptmann GÜnter JUNG (120 men), a cycling unit also stationed in Saint-Pierre, or to the Fest Nachr Stab 2/6 (2nd company of the 6th staff signal battalion), based in Saint-Georges.
A company of 163 Italians (former Bordeaux submariners), from the San Marco battalion, commanded by the tenante di vascello Massimo DI PACE, mainly takes care of administrative tasks and easements for the benefit of their allies, who do not grant them only a limited confidence since the capitulation of Italy.
The remainder comes from a reinforcement of the Marine Regiment Zapp from La Rochelle (250 men), sent on April 15, 1945 and from combatants who managed to escape capture, after crossing the Pertuis de Maumusson on April 18, 1945, during the fighting of Royan.
On the eve of the landing, according to the own estimate of the korvettenkapitän SCH-EFFER, the ammunition is sufficient to last 2 years; but the supply, 2 months. In addition, the morale of the German garrison is very low, since for several days, the positions have been receiving a daily deluge of artillery. Several positions in the north and west of the island were dismantled between September and December 1944 to be redeployed to the south and east. Thus, the powerful positions of the Pointe de Chassiron are almost abandoned, fake wooden cannons replace the real ones. Several buried positions, connected by trenches and defended by mines and barbed wire, were built along the main axes that connect the municipalities of the island. A total of 32,000 mines or booby-trapped devices of all types were planted in Oléron.
On April 24, 1945, General de Corps d’Armée Edgard de LARMINAT, established in Cognac in his operations order n° 9, the execution plan for the liberation of Oléron. To this end, was set up on March 13, 1945, the “Oleron March Division”, entrusted to Brigadier General René MARCHAND. It is composed for the infantry of 3 battalions of the 158th Infantry (ex Armagnac brigade and ex Bigorre / FFI battalion), 2 battalions of the 50th R.I (ex RAC / FFI brigade), a battalion of the 131st R.I (ex maquis of Mussy Grancey in Aube), the 6th Battalion of North African Riflemen (6th B.P.T.N.A composed of North Africans liberated from the camps of Gironde), the Battalion of Fusiliers Marins de Rochefort (ex Corps Francs Marins / FFI) , the Franc Marin Armagnac Group (ex corps francs “Marennes et Seudre”, Lucien LECLERC, Camille ROUDAT and Antony DUBOIS) and the Corps Franc d’Aviation “Le Gaulois”. Almost all of the recruits came from the maquis, the regular army being absorbed by the fighting in the Vosges. Dissension very quickly appeared between General MARCHAND’s staff and the corps commander of the 158th Infantry Regiment, Lieutenant-Colonel Henri MONNET, anxious to spare the lives of his men as much as possible. To cut short the recalcitrant, Lieutenant Colonel René BABONNEAU, an active officer who served in the ranks of the Foreign Legion, was appointed corps commander of the 158th Infantry Regiment. But having no control over the men, he asked his predecessor to keep his job, offering him to become his technical adviser.
The initial sea landing is scheduled for April 29, but weather conditions will postpone the operation for 24 hours. In the meantime, 24 American barges of the LCVP (Landing Craft Vehicle Personnel) type were delivered by rail to Rochefort, then transported by the Bellevue canal from Charente to La Seudre to Marennes.
From April 17, 1945, several aerial bombing sorties were carried out. On the afternoon of the 17th, Martin B26C Maraudeur twin-engine medium bombers from the 11th Saint-Dizier bombing brigade intervened on the citadel of Château-d’Oléron, hit by 96.5 tons of bombs. On the 19th, it was the turn of the Pointe de Gatseau, and again the citadel of the Château, as well as Boyardville, treated from the base of Cognac, by the Air Forces of the Atlantic (FAA): fighter groups “Saintonge ” (Spitfire Mk V) and “Vendée” (Dewoitine 520 and Douglas A 24), bombardment groups “Aunis” (Junker Ju88A), reconnaissance group “Périgord” (Morane-Saulnier 500, Nord 1000 and Potez 631), placed under the command of Brigadier General Edouard CORNIGLION-MOLINIER; reinforced by Naval Air Group No. 2 (G.A.N 2) of frigate captain Francis LAINE, equipped with 32 Douglas SBD Dauntless, and the 26th squadron of the R.A.F, equipped with Mustang. On April 25, the Giraudière battery received 31.5 tons of bombs dropped by 10 Ju 88s and 23 Douglas SBDs, while Pointe d’Ors was attacked by 12 Spitfires in a dive. On 28 April, 11 Ju 88s bombed the Flak battery at Boyardville with 19 tons of bombs, while 12 Spitfires dealt with that at Saint-Pierre.
The 13th Field Artillery Brigade (13th U.S. Artillery Brigade) commanded by Brigadier General BANK, composed of the 999th FAB, 235th FAB, 514th FAB and 257th FAB (Field Artillery Battalion) began the same day the systematic shelling of German positions at the using its 155 and 203 mm howitzers.
Similarly, a “French Naval Task Force”, commanded by Rear Admiral Joseph RÜE, was hastily formed in England on April 12, 1945 to provide support to ground troops from the cruiser Duquesne, the torpedo boats Fortuné, Basque and Alcyon, the escorts Aventure, Surprise, Découverte, Hova, the Amiral Mouchez minesweeper group and the 31st (Canadian) Minesweeper Flotilla. These buildings cross from April 27 off the west coast of the island, and engage the concrete positions thanks to the 4 turrets of 203 mm of the cruiser Duquesne (700 rounds fired), guided by the planes of G.A.N 2.
On April 25, 1945, two groups of resistance fighters commanded by Captain LECLERC infiltrated the island with radio means in order to provide information on the positions and movements of the enemy and to coordinate sabotage actions (cutting of telephone lines, destruction means of transport and setting up roadblocks at crossroads). The same day, the 1st group of the 12th Artillery Regiment took position near the beach of Marennes.