When the German Troops arrived in Soulac after the armistice of the 25th of June 1940, they took the four 164 mm model 1887 guns emplaced at Les Arros, a French battery that had been recently built and had only time for a first combat shooting before the hostilities ceased, opening fire against the German guns at Fort du Chay. Although they had removed the breech locks of guns so that they could not be reused by the enemy, the German experts found it easy to refit those ancient but effective naval guns and they soon became part of the Atlantic Wall, being operated by a total of 120 MAA 618 artillerymen. The fire control centre remained virtually unchanged, as well as the gun emplacements, which were initially made of iron plates pits buried in the sand and then, after 1942-1943, covered by concrete M-270 type casemates. At that period, a total of 20 concrete pillboxes and 15 barracks were erected, making up a real fortress including troop shelters, flanking casemates with anti-tank guns, emplacements for anti-aircraft guns, an infirmary, a kitchen, and a water cistern, among many other things. It was stocked by the following weapons:
- 4 x 164 mm guns.
- 2 x 75 mm FK231 guns.
- 2 x AA 20 mm Flak 28 Oerlikon guns.
- 2 x AA 20 mm Flak Vierling quadruple guns.
- 1 x 37 mm SKC 230 gun.
- 4 x 50 mm mortars.
- 2 x 150 cm searchlights and a marine search radar type FuMO 24 Seetakt.
- 30 flamethrowers located at fixed defensive emplacements.
- 9 MG34 machine guns at "Tobruk" emplacements over the concrete casemates.
- All kinds of light weapons: rifles, submachine guns, grenades.
- An anti-tank and anti-personnel minefield around the battery perimeter.
The command post of the whole coastal artillery of the Pointe de Grave was established at Les Arros under the command of Captain Schillinger, although the battery was led by Lieutenant Erwin Arndt who, according to French historians, was a fervent Nazi. In autumn 1943, the MAA 618 was reinforced by several Soviet ex-prisoners of war from the 657th battalion of Don Cossacks, who were on garrison duty in the area, of which 13 men became part of Les Arros personnel. In March 1944, four of those Osttruppen met at command bunker M151 and hatched out a plan to kill 40 non-commissioned officers and other enlisted personnel. The attack, which had certain suicidal features, was to take place at the barracks located behind the battery, known as "Bunker village". However, one of the Russian soldiers, called Furmantschek, reported their intentions to Captain Schillinger's assistant and Lieutenant Arndt, after ordering a search of the place, discovered a big quantity of explosives. The four plotters were arrested and executed at the Arros battery by a firing squad commanded by Lieutenant Arndt himself. Later on, another six conspirators were arrested and executed in the same way. No one knows what happened to the other three men, one of whom was the informer.
After the Médoc front was established in autumn 1944, the pocket of resistance at the Pointe de Grave was definitely closed and the old marine guns of Les Arros were removed from the big concrete casemates and emplaced outside to turn them at the interior, pointing towards the French troops. Those guns were fired unceasingly since the start of the french operations to free Pointe de Grave, which took place on the 14th of April 1945.
On the 18th of April 1945, the Régiment Mixte Marocain Étranger, where the Gernika battalion was included, entered into Soulac-sur-Mer from the coast and along the railroad track, but they faced a German counterattack at L´Amélie. Other units had a much more difficult time, as for instance the Somalian AEF Regiment of the 1st Free French Division, which was attacked by a heavy fire of machine guns and mortars as they crossed an anti-tank ditch, causing more than one hundred casualties. After the liberation of the coast village, the units positioned themselves just opposite the Arros Battery and their garrison had to endure two long days of heavy air raids, repelling all the attacks from the French infantry. Those were the last combat shots their 164 mm guns would fire against the French troops.
At 7 pm on the 19th of April, when their second day of resistance was about to finish, the 618 MAA artillerymen at Les Arros finally saw themselves forced to yield to the attack of the French units. Those units were supported by Somua S-35 tanks from the 13th Dragons regiment, which defeated all the areas of resistance until the crossfire of machine guns from the battery ceased. It was a combined attack in which both the Gernika and the Libertad battalions took part, as well as three companies of the 131st Infantry Regiment. The attackers spread all around the battery, taking the pillboxes one after another. After the Gernika battalion had reached the command bunker, Lieutenant Arndt and his officers were executed. Their dead bodies were photographed by André Puytorac, the renowned photographer from Bordeaux. As a result of those two days of combat, the MAA 618 lost a total of 26 men and almost one hundred were made prisoners, many of whom were injured.
A view of Les Arros battery after the action of April 1945. See the last emplacements of the old naval guns -outside the concrete casemates- so that they could be fired at the French troops stationed at the Médoc front. The shooting distance of those guns could reach 20 kilometres (http://maquisardsdefrance.jeun.fr/).