Operation Jupiter III
The Attack on the Île d'Oléron
30 April/1 May 1945
The first Operation Jupiter was a plan originating in 1941 for an invasion of northern Norway and Finland by the Allies; but it was revised and updated in May 1942. The first versions of the plan were code named Operation Dynamite, Operation Ajax and Operation Marrow. Devised and vigorously promoted by Churchill, the plan was opposed by all the senior British and Allied commanders, who considered it impractical because of insufficient air support and of limited value. The scheme was eventually abandoned in favour of the landings in Normandy in 1944.
Operation Jupiter II was an offensive by VIII Corps of the British Second Army from 10 to 11 July 1944. The operation took place during the Battle of Normandy . The objective of the 43rd (Wessex) Infantry Division (Major-General Ivor Thomas) was the villages of Barob-sur-Odon, Fonyaine-Etoupefour, Château de Fontaine-Étoupefour and to recapture Hill 112. An attached brigade of the 15th (Scottish) Infantry Division was to take Eterville, Maltot and the ground up to the River Orne; after which the tanks of the 4th Armoured Brigade, supported by infantry, would advance through the captured ground and secure several villages to the west of the River Orne.
The German garrison under the command of Vice Admiral Ernst Schirlitz, reporting to the La Rochelle sector, was led from January 1945 by Korvettenkapitän Alfred Graf Schiltz von Görtz und von Wrisberg, German headquarters was located on Avenue Bel-Air in Saint-Pierre d'Oléron. The garrison comprised of approximately 2,200 men, of whom 1,380 were from the Kriegsmarine.
They mostly belong to the Leichte Marine-Artillerie-Abteilung 687 (Light Coastal Artillery Group 687) commanded by Korvettenkapitän Werner Schaeffer. This artillery group comprises 3 mobile intervention companies (a total of 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 consist of 16 horse-drawn 75mm guns and 6 Schneider 155mm howitzers..Leichte schützen-kompanie (light support company), consisted of: 7 x 20mm anti-aircraft guns and 11 x 81mm mortars and finally an anti-tank company equipped with 12 PAKs of 37 to 50mm.
320 men were part of Marine-Flakartillerie-Abteilung 812 (Naval Anti-Aircraft Artillery Group 812 or MaFla 812); belonging to Marine-Flak-Brigade V (headquartered in Saint-Nazaire). Created in March 1942 between the islands of Ré and Oléron, this brigade consisted of three batteries (two of which were equipped with 75mm Flak M35 Vickers guns) and a half-company of six 150cm Siemens searchlights. The entire unit was under the command of Oberleutnant Kroner. Finally, the soldiers of 2 Komp/3 Funk-Mess-Abteilung (2nd Company of the 3rd Radio Surveillance Battalion) manned the radar installations with a range of 60 kilometers and optical transmission equipment at Pointe de Chassiron.
350 men from the Wehrmacht serving mostly within the Heeres Kotier Artillerie Abteilung 1280 (Army Coastal Artillery Group 1280) of Hauptmann Muller; which had 4 firing batteries (230 men) distributed at Douhet (1/HAA 1280), Saint-Denis (2-3/HAA 1280) and Chaucre (4/HAA 1280). 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 signals battalion), located in Saint-Georges.
A company of 163 Italians (former submariners based in Bordeaux), from the San Marco battalion, commanded by the Tenante di vascello Massimo Di Pace, mainly takes care of administrative tasks and services for the benefit of their allies, who have only limited confidence in them since the capitulation of Italy.
The remainder came from a reinforcement of the Marine Regiment Zapp from La Rochelle (250 men), sent on April 15, 1945 and from fighters who managed to escape capture after crossing the Pertuis de Maumusson on April 18, 1945, during the fighting at Royan.
On the eve of the landings, according to Korvettenkapitän Schäeffer 's own estimate, ammunition was sufficient to last two years! But supplies, only two months! Furthermore, the morale of the German garrison was very low, as the positions had been receiving a daily artillery barrage for several days. Between September and December 1944, several positions in the north and west of the island were dismantled and redeployed to the south and east. Thus, the powerful positions at Pointe de Chassiron were virtually abandoned, with wooden dummy guns replacing the real ones. Several underground positions, linked by trenches and defended by mines and barbed wire, were constructed along the main roads connecting the island's towns. In total, 32,000 mines or improvised explosive devices of all types were laid on Oléron.
French/Allied Support
Atlantic Air Forces (FAA), under the command of Brigadier General Edouard Cornigion-Molinier, which had been created in Cognac in March 1945, included the fighter-bomber groups 1/18 "Vendée" (15 Dewoitine 520s and 7 Douglas A24 Dauntless) and 2/18 "Saintonge" (29 Spitfire Mk Vs), the bomber group 1/31 "Aunis" (12 Junkers 88As and various recovered aircraft), the reconnaissance group 3/33 "Périgord" (24 Fieseler Storches and 3 Siebel 204s).
Naval Air Group No. 2 (GAN 2) of Commander Francis Laine, equipped with 21 Douglas SBD 5s and by the 26th squadron of the RAF, equipped with 20 Mustangs.
In mid-March 1945, Douglas SBD 5s of GAN 2 set fire to the German coastal minesweeper FO 15 as it was being evacuated to La Pallice.
French Naval Task Force, commanded by Rear Admiral Joseph Rüe including the cruiser Duquesne, the torpedo boats Fortuné, Basque and Alcyon, the escort vessels Aventure, Surprise, Découverte and Hova, the minesweeper group Amiral Mouchez, and the 31st (Canadian) Minesweeper Flotilla. The fire from these ships guided by the planes of GAN 2.
Preparations and the attack
On the afternoon of April 17, American twin-engine Martin B26C Marauder medium bombers of the 8th Air Force bombed the Château sector, which was hit by 96.5 tons of bombs .
On April 19, 10 Ju88s from the Aunis group bombed La Perrotine, the Saint-Pierre command post, Pointe de Gatseau, and again the Château citadel, as well as Boyardville.
On April 23, the Giraudière battery received 31.5 tons of bombs dropped by 10 Ju 88s and 24 Douglas SBDs, while Pointe d'Ors (listening post) was attacked by 12 Spitfires both strafing and bombing.
On April 25, 1945, two resistance groups commanded by Captain Leclerc infiltrated the island with radio equipment to gather intelligence on enemy positions and movements and to coordinate sabotage operations (cutting telephone lines, destroying transportation, and setting up roadblocks at intersections).
On April 28, 12 Ju 88s bombed the La Perrotine Flak battery at Boyardville with 19 tons of bombs, while 12 Spitfires attacked the Saint-Pierre battery.
On Monday, April 30 at 4:56am, Operation "Jupiter" was launched. 24 LCVPs commanded by Lieutenant Commander Tanan (US Army), 22 DUKWs, which had arrived in Marennes the day before from Le Havre and 42 fishing boats, originating from Marennes, Galon d'Or, Port-Lambert, Arcachon and Saint-Jean-de-Luz, forming four wave elements, spaced 5 minutes apart, set off from the port of La Cayenne in Marennes, guided by fishermen from Oléron and waited at the mouth of the Seudre.
The artillery bombardment began immediately with the firing of 168 guns ranging from 90mm to 220mm from the US 13th Field Artillery Brigade (part of General Devers' US Sixth Army) commanded by Brigadier General Bank, composed of the 999th FAB (Field Artillery battalion), 235th FAB, 514th FAB and 257th FAB; reinforced by six batteries from the 1st Marine Artillery Regiment and one battery from the 16th Anti -Aircraft Ground Forces Group. The batteries were deployed between La Tremblade and Marennes, covering the area from Pointe de Gatseau to Pointe Manson.
At 5:00am, a radio message to the La Laudière command post instructed the 17 resistance groups to begin their attack. Numerous telephone cables, particularly in the north of the island, were cut.
At 6:02am, when the outside temperature reached -6°, the first assault wave under the command of Lieutenant Joseph Dupin de Saint Cyr, landed on Gatseau beach in a cloud of smoke, under enemy fire from a combat group commanded by Oberleutnant Klaus Marx, slightly west of the lifeboat house, on the site of the former American seaplane base, built in 1917.
The sappers of Captain Perret's mine-clearing section (3/151st Engineers) created breaches in the minefields. Two companies of marine riflemen, commanded by Lieutenant Commander Michel Fouchier, immediately rushed in, heading towards the Lannelongue sanatorium, and the Hummel Lifesaving Center along with the infantrymen of the 2nd Battalion of the 50th Infantry Regiment, commanded by Captain Jean-Marie Poitevin, who were tasked with securing the southern tip of the island. Artillery fire was extended to a range of 400 meters, while the German artillery remained silent. Blockhouse Ro 506 Hase at Pointe de Gatseau was captured, but the position was empty. The marine riflemen of the 1st and 2nd companies were already hard at work, seizing the Lifesaving Center, which housed 30 men, two 155mm guns, and two 75mm guns.
At 6:07am, the second element of the first assault wave was landed in turn, about 600m east of the first elements due to the current and the smoke screens that masked the area.
At 6:15am, a new assault wave, commanded by Lieutenant Colonel Gabriel Termignon, carrying the 250 men of the 3rd Battalion of the 158th Infantry Regiment (formerly the 1st Gers Regiment of the FFI), landed on the island, quickly joined by heavy machine gun sections and mortar groups. They established a link-up with the marine riflemen at Lannelongue.
At 6:20am, enemy fire swept across the beach and the edge of the forest. It came from a 20mm Flak 30 on wheels, which was silenced shortly afterward by elements of the Lelong Company of the 50th Infantry Regiment.
At 6:30am. the final assault wave, including the 3rd Battalion of the 50th Infantry Regiment, arrived, followed by medical personnel and light vehicles.
At 6:35am, two Spitfires from the Saintonge Group bombed the La Giraudière blockhouse.
In 45 minutes, 675 men (4 assault waves) had been landed to establish a solid beachhead. Unfortunately, six men were lost - two petty officers (LCVP pilots), two soldiers from the 158th Infantry Regiment and two more from 50th Infantry Regiment, along with several wounded.
At 7:30am, the bridgehead was solid, extending 2 kilometers into the Saint-Trojan forest, on the southwestern edge of the Brys. Reinforcements continued to pour in, the divisional infantry command post landed at 7:45am and set up at the sanatorium's water tower.
Shortly after 8:00am, six Douglas SDB 5s from the Carrier Strike Group (3rd Fighter Squadron) conducted a reconnaissance flight to La Pallice to ensure that reinforcements were not being sent. They were not; all the ships in the port had their lights off. On the return flight, despite the low cloud ceiling and drizzle, the flak battery north of Saint-Pierre was attacked. A mistaken target unfortunately resulted in civilian casualties among the residents of the Allées district. Also at 8:00 am, the French Naval Task Force went into action and bombarded enemy positions all over the island.
By 9:30am, at the end of the tide, 8 tons of infantry ammunition, 4 Dodge trucks, 2 Jeeps, and 1 Nebelwerfer (150mm multiple rocket launcher) were unloaded and nearly 2,400 men (from 50th, 158th, and 131st Infantry Regiments plus some from 6th BPTNA) were ready for combat. The advance could begin.
Two groups were formed: the "Western group" of Lieutenant Colonel Rodolphe Cezard, alias "RAC", which included the 2nd and 3rd battalions of the 50th RI commanded by battalion commanders "Roland" Clee and René Tallet known as "Violette" (ex maquis of North Dordogne), the Rochefort marine rifle battalion of Lieutenant Commander Dupin de Saint Cyr, a company of the 151st Engineer Regiment and 2 groups of 75 mm guns (I assume 75mm pack howitzers, but they could well have been Pak40s!!) from the 32nd Artillery Regiment. This group received the mission to advance on three axes, along the palisades, through the Saint-Trojan forest to the Isthmus of Allassins.
Lieutenant Colonel Monnet's "Eastern Group", composed of 3 battalions of the 158th Infantry Regiment, a company of the 151st Engineer Regiment and the 1st group of 75mm PAK40 anti-tank guns of the 12th Artillery Regiment (formerly the Z resistance network of Royan), was to seize the blockhouses of Pointe de Menson south of Saint-Trojan (the objective was reached at 10:00, about thirty prisoners were taken), then advance towards the town center of Saint-Trojan while controlling the access to Château-d'Oléron.
At 10:15am, the Huhn position at Menson Point was taken without a fight by the 3rd Battalion of the 158th Infantry Regiment (Commander Louis Dorbes), ten Germans were captured.
At 12:00am, the center of Saint-Trojan was liberated by the 3rd Battalion, 158th Infantry; while Saint-Trojan-Plage was reached by the Western Group, which, despite the difficult advance through the woods, encountered only light resistance at the Forestry House. At the same time, the first Somua S-35 tank was unloaded at the Lannelongue slipway.
At 12:40am, the 4th Squadron of the 18th Chasseurs à Cheval and 18 of its Bren Carrier tracked vehicles were in action at Lannelongue, immediately followed by the 158th Infantry Regiment and elements of 6th BPTNA.
In the forest, Courant`s section of the 9th Company of the 50th Infantry Regiment encountered fierce resistance near the Brys forester's lodge. Fifty entrenched Germans blocked the advance, but ultimately ten were killed and forty captured.
Around 1:00am, the Allassins isthmus was practically reached, but upstream from Grand-Village, between departmental road 126 and the west coast, a vast minefield (800m x 1000m) had been laid during the winter of 1944; behind which Germans had entrenched themselves, blocked the advance. To the east, the maze of salt marshes extended this insurmountable obstacle. Three men from 10th company, 50th Infantry Regiment were killed and several others seriously wounded. Mortars and heavy machine guns were used to dislodge the enemy, but it took the intervention of 86 B-26C Marauder bombers from the 42nd US Bomb Wing of the 1st Tactical Air Force, delivering 103 tons of cluster bombs, between 4:00 and 4:50pm, to definitively neutralize the minefield and finally allow the advance to resume.
The bombers used the “Shoran system”, which allows for precise bombing in zero visibility thanks to radio beacons placed on the ground that emit echoes.
By 5pm, the marines established themselves at Allassins, north of Grand-Village, where they came under fire from the Ro 541 Kater battery on La Giraudière beach. This fire, which resulted in the loss of 3 marines and 7 wounded, prompted a response from the marines' mortars and necessitated the deployment of two companies from the 6th BPTNA (North African Parachute Battalion) under Commander Marcel Govys to provide immediate protection for the village. The 9th Company of the 3rd Battalion of the 50th Infantry Regiment managed to silence the La Giraudière battery and captured 7 Germans.
The hamlet of Trillou was occupied around 6:00pm.
The Eastern Group, for its part, reached Le Château-d'Oléron just as Captain Adrien Capin's commandos (1st Battalion of the 158th Infantry Regiment) landed to hold Ors. The advance towards Dolus continued; the Lerche position at La Dresserie was bypassed, but the Ors headland, Ro 503 Hermelin, with its 75mm gun, 47mm gun, machine gun, and 10 crewmen, was captured.
At 7:50pm, the reconnaissance elements of the 18th Chasseurs, which had advanced to the outskirts of Dolus, were attacked at La Dresserie and forced to retreat. However, the resistance fighters who had begun reducing the Saint-Pierre command post were galvanized and continued their guerrilla actions. The Château was finally liberated around 8:00pm.
At 8:30pm, a strong German counter-attack, led by a German intervention company based in Dolus and equipped with mortars, grenade launchers, machine guns, and two 75mm guns, targeted the marines stationed at Trillou and Les Allassins. The marines, suffering four dead and ten wounded, withdrew to Grand-Village where they were reinforced by a reserve company from the 6th BPTNA. The marines then launched another attack on Petit-Village to expand their perimeter, forcing the Germans to retreat.
By 11:00pm, the 2nd battalion of the 158th RI reached La Gaconnière, while elements of resistance fighters commanded by Captain Leclerc settled safely in La Menounière.
The first day of Jupiter III had been a success, 3,200 men had been landed along with much heavy equipment including two Somua S-35s of 13e Dragons commanded by Lieutenant de Chalembert (transported by special pontoons built by the 92nd Engineers) – here it should be noted that 5 Somuas were earmarked for the operation, but a lack of suitable transport meant only the two tanks were actually ferried to the island.
18 Bren carriers belonging to 4th Squadron of 18th Chasseurs de Cheval commanded by Lieutenant Jacques de Fleurieu were also ferried to the island to assist with transportation and supply. The total French casualties amounted to 18 killed and 55 wounded, as well as 6 civilian deaths. The Oléron Division captured 180 prisoners and the Resistance had captured another 212, who were transported throughout the day to Gatseau beach.
1st May
Around 1:00am, the 207 members of the Fournier commando, composed of former marine commandos from the "Antony Dubois," "Camille Roudat," and "Marennes et Seudre" (Captain Elie Rouby) units, regrouped within the "Groupe Franc Marin Armagnac" (GFMA), landed at La Vieille Perrotine, between two German positions. The flotilla of 16 local boats that transported them came from Le Chapus. Two columns, formed by Lieutenant Commander Lucien Fournier and Captain Jean Poirier, advanced, one towards Arceau and La Cotinière (to link up with Captain Leclerc, who had requested reinforcements), while the other headed towards Les Allards, along the Arceau and Dolus channel (reached at 5:00am but liberated at 10:00am). A few German soldiers positioned in the oyster huts attempted to hinder the advance along the Arceau channel with machine-gun fire, wounding three, but a mortar salvo dislodged them. The GFMA linked up with the 2nd Battalion of the 158th Infantry Regiment around 11:00am at La Gaconnière. During the day, it had reduced the enemy positions at Méré (5:30am), La Rémigeasse (at 11:00am) where it linked up with the 7th Company of the 50th Infantry Regiment, Pierre-Levée and Moulin des Landes. This unit alone captured nearly 600 prisoners.
At 8:00am, the advance of the Cezard and Monnet groups resumed from Grand-Village after an artillery barrage from the batteries of the 12th and 32nd Artillery Regiments (250 shells), joined by Captain Arene's Nebelwerfer (40 rockets). The Germans holding the Allassins positions withdrew during the night.
Around 11:30am, the 7th Company of the 50th Infantry Regiment (Violette Battalion) was engaged by machine-gun fire at La Rémigeasse. Private Marcel Normandin, from Bourcefranc, was hit directly and died instantly. He was the last French casualty of Operation Jupiter.
At noon, La Cotinière was liberated, shortly after the coastal battery Ro 512 Mammuth was taken by the assault of the Poirier section of the GFMA and the resistance group of Captain Leclerc.
At 1:00pm, a new skirmish with Germans barricaded in a villa in La Rémigeasse was reported. Eight men from the Fournier Commando, supported by two from the Roudat Commando, reduced the position.
The carriers of the 18th Regiment Chasseurs d`Cheval and the platoon of tanks from the 13th Dragoons, of Capt. d'Aboville, advanced towards Saint-Pierre in support of the 2nd Battalion of the 131st Infantry Regiment. Captain Bourguignon, accompanied by resistance volunteers, launched an attack against the Inselkommandantur (island command headquarters). They captured about twenty officers, including the island's military commander, and some thirty non-commissioned officers, whom they immediately locked in the cinema. At 2:30pm, the town was completely in French hands!
After much hesitation, the German commander finally agreed to give the order to surrender to all his troops stationed in the north of the island. Two armored vehicles (probably a couple of the Bren carriers mentioned above) were used to ferry the German and French officers back and fore for negotiations. They secured a ceasefire at Chaucre, immediately occupied by the 2nd battalion of the 131st RI Saint-Georges, where the 2nd battalion of the 158th RI took up position (4.30pm); at Cheray and Les Boulassiers, surrounded by marine infantry supported by the 13th Dragoons Somuas (4:30pm), at Le Douhet and Saint-Denis was taken by 2nd battalion of the 131st RI, closely supported by the guns of 32nd Artillery Regiment (5:30pm) and at Chassiron which was invested by the 6th BPTNA (6:00pm). Approximately 500 Germans laid down their arms in the Boultoir woods near Cheray. However, the garrisons at Les Saumonards and Boyardville refused to surrender.
Thanks to the complicity of a Feldwebel Bagger, the group led by resistance fighter Emile Schwartz managed to neutralize the 11 armed mines intended to destroy the port of Boyardville and seized the swing bridge over the port. For five hours, fierce fighting raged between the men of the 3rd Battalion, 158th Infantry (Commander Dorbes) and the heavily entrenched Germans who had ample ammunition, both within the port and around the last two forts, before the enemy finally surrendered at approximately 8:15pm.
The final skirmishes took place around Fort des Saumonards, totally surrounded by the 3rd Battalion of the 158th Infantry Regiment, the garrison finally capitulated around 10:00pm.
The conquest of the Île d'Oléron was complete.
By the evening of May 1st, the results of Operation Jupiter were as follows: of the 8,882 French combatants involved, 18 were killed (plus at least 6 civilians) and 56 wounded; the Germans lost approximately 50 men, with 60 wounded and 1,700 taken prisoner (including 40 officers). Fifty enemy artillery pieces were captured. Allied artillery fired over 27,874 shells, while 800 tons of bombs were dropped by aircraft.
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