'Firebrand' was the Allied plan for Free French forces under the command of Général d’Armée Henri Giraud to invade and retake the island of Corsica after the occupation of southern Italy and the establishment of airfields in the Rome area to provide the requisite fighter cover over the island (12 September/3 October 1943).

The plan was finally undertaken within the context of 'Norman' (i) for the seizure of Sardinia as well as Corsica. The Axis forces on Corsica before Italy’s armistice with the Allies were commanded by Generale di Corpo d’Armata Giovanni Magli, whose garrison included his own VII Corpo d’Armata (Generale di Brigata Arnaldo Bonelli’s 44a Divisione fanteria 'Cremona' and Generale di Brigata Bartolomeo Pedrotti’s 20a Divisione fanteria 'Friuli') as well as Generale di Brigata Bartolomeo Petrotti’s 225a Divisione costiera and Generale di Brigata Attilio Lazzarini’s 226a Divisione costiera. However, after the evacuation of the German forces on Sardinia to Corsica on 8 September, the primary fighting forces on the French island were the 12,000 or so men of SS-Brigadeführer und Generalmajor der Waffen-SS Karl Herrmann’s (from 18 September SS-Standartenführer Herbert von Obwurzer’s) 1^st SS Sturmbrigade 'Reichsführer-SS', elements of Generalmajor Theodor Graf von Sponeck’s 90^th Panzergrenadierdivision and substantial Flak units under the overall command of Generalleutnant Fridolin Ritter und Edler von Senger und Etterlin. These German forces started to arrive on the island after Benito Mussolini, the Italian dictator, had been deposed and imprisoned in July 1943.

The Germans formally took over the occupation on 9 September 1943, the day after the armistice between Italy and the Allies. While their leaders were ambivalent, most of the Italian troops remained loyal to King Vittore Emanuele III, and some of them fought (primarily at Teghime, Bastia and Casamozza) alongside the French resistance against the German troops until the liberation of Corsica on 4 October 1943. Meanwhile, the French resistance aimed to establish control of the mountains in the island’s centre as this would prevent the comparatively small number of German occupation troops from moving from one coast to the other, and thus facilitating an Allied invasion.

When the Italian armistice was announced, the island’s resistance forces, which numbered some 20,000 men and had received more than 10,000 automatic weapons by air drop or submarine delivery since December 1942, occupied Ajaccio and joined Magli in calling for assistance from the Free French forces in North Africa. Meanwhile the Germans drove the Italians out of Bonifacio and Bastia.

In Algiers, Giraud decided somewhat reluctantly that his forces should aid the island’s rising against the Germans. With the help of Contre-amiral André Georges Lemmonier, he improvised a small expeditionary force whose leading elements arrived during the night of 12/13 September: these were 109 men of the Bataillon de Choc, who had been packed tightly into the submarine Casabianca and landed near the village of Piana in the north-western part of the island. On the following day the large destroyers Fantasque and Terrible landed more than 500 more men of the same battalion, and then maintained the shuttle service together with the destroyers Tempête and Alcyon. Then the light cruisers Montcalm and Jeanne d’Arc joined the effort, despite the threat posed by the Luftwaffe’s recent introduction of a radio-guided glide bomb, one of which had just sunk the Italian battleship Roma on passage to Malta.

The arrival of French troops on the island prompted the Germans to react, and they began attacks on the Italian troops as well as French resistance forces on Corsica. The Corsican and French resistance fighters, together with the 44a Divisione fanteria 'Cremona' and 20a Divisione fanteria 'Friuli', engaged in heavy combat with the SS Sturmbrigade 'Reichsführer-SS' and 90^th Panzergrenadierdivision, supported by the Italian 12/184o Reggimento paracadutisti 'Nembo' and most of the 3/185o Reggimento paracadutisti 'Nembo', which arrived from Sardinia, and then retreated through Corsica from Bonifacio toward the northern harbour of Bastia.

Although the Germans had initially decided to hold Corsica, on 12 September they had undergone a change of mind and orders were issued for the German forces to be concentrated round Bastia for the 'Eisbär' (iv) seaborne evacuation to Livorno and Piombino in Italy, and to the island of Elba off the western coast of Italy. This move had been completed by 3 October with the Germans' now well-honed evacuation skills. With the help of their new Italian allies, the 5,000 infantry and goumiers of Général de Division François Adolphe Laurent Sevez’s 4ème Division Marocaine de Montagne, which had started to arrive at Ajaccio by sea on 13 September, had managed to disperse the German rearguard, but were quite unable to cut off the main force.

By 27 September the French had landed some 6,300 men but the British and Americans, fully committed in the area to the south of Naples, were too late to intervene. Thus this small-scale German evacuation recovered 21,100 men by air and other 6,250 men plus 1,200 prisoners of war by sea before its end on 3 October, when they abandoned 700 dead and 350 men to be taken prisoner. The Germans lost 55 transport aircraft and 17,000 tons of shipping in the course of the operation. The sacrifice of 222 Frenchmen and 637 Italians, the reoccupation of Corsica gave the Allies a strategic position of the first importance, with 17 airfields capable of taking and maintaining 2,000 aircraft: the USAAF moved onto the island within a matter of months.