At the outbreak of World War II, Charles de Gaulle was put in charge of the French 5th Army's tanks (five scattered battalions, largely equipped with R35 light tanks) in Alsace, and on 12 September 1939, he attacked at Bitche, simultaneously with the Saar Offensive.

In late February 1940, Paul Reynaud told de Gaulle that he had been earmarked for command of an armoured division as soon as one became available. In late March, de Gaulle was told by Reynaud that he would be given command of the 4th Armoured Division by 15 May. The government appeared likely to be restructured, as Édouard Daladier and Maurice Gamelin were under attack in the aftermath of the Allied defeat in Norway, and had this happened de Gaulle, who on 3 May, was still lobbying Reynaud for a restructuring of the control of the war, might well have joined the government. By 7 May, he was assembling the staff of his new division.

De Gaulle founded and headed several organization during the course of the war to administer the operation of Free France, starting with the Empire Defense Council days after Vichy capitulated in June 1940, and ending with the Provisional Government, which provided the transition from the liberation of France through the first elections in 1945, to the establishment of the Fourth Republic in 1947.

Battle of France

Division commander

Nazi Germany attacked France on 10 May 1940. De Gaulle led his new division on 12 May. The Nazis broke through at Sedan on 15 May. That day, with three tank battalions assembled, less than a third of his paper strength, he was summoned to headquarters and told to attack to gain time for General Robert Touchon's Sixth Army to redeploy from the Maginot Line to the Aisne. General Georges told him it was his chance to implement his ideas.See, e.g.,

De Gaulle commandeered a retreating cavalry. The attack at Montcornet, a key road junction near Laon, began around 04:30 on 17 May; outnumbered and without air support, he lost 23 of his 90 vehicles to mines, anti-tank weapons, and Stukas. On 18 May he was reinforced by two fresh regiments of armoured cavalry, and attacked again on 19 May, where his forces were once again devastated by German artillery. He ignored orders from General Georges to withdraw, and demanded two more divisions from Touchon, who refused his request. Although de Gaulle's tanks forced German infantry to retreat to Caumont, the action brought only temporary relief and did little to slow the spearhead of the German advance. Nevertheless, it was one of the few successes the French enjoyed while suffering defeats elsewhere across the country.Ledwidge pp. 50–52

He delayed his retreat until 20 May. On 21 May, at the request of propaganda officers, he gave a talk on French radio about his recent attack. In recognition for his efforts de Gaulle was promoted to the rank of temporary (acting, in Anglophone parlance) brigadier-general on 23 May 1940. Despite being compulsorily retired as a colonel on 22 June (see below) he would wear the uniform of a brigadier-general for the rest of his life.Lacouture writes that after the war he was "mythically a general to all eternity, but legally a retired colonel". Early in 1946, just after his departure from office, War Minister Edmond Michelet wrote to him that Prime Minister Félix Gouin wanted his rank to be as high as possible (which Lacouture takes to mean Marshal of France). De Gaulle wrote back that it was "impossible to regulate a situation absolutely without precedent," that the situation had continued for 5 years 7 months and 3 days and that it would be "strange, even ridiculous" to rectify his rank for administrative reasons now. As the royalties for his War Memoirs were paid to the Anne-de-Gaulle foundation, he and his wife had to live off his pension as a retired colonel in the 1950s. His wife was reduced to selling family silverware to help make ends meet.[Lacouture Vol 2, pp. 128, 156-7] De Gaulle attacked the German bridgehead at Abbeville on 28–29 May, taking around 400 German prisoners in the last attempt to cut an escape route for the Allied forces.

The future General Paul Huard, who served under de Gaulle at this time, recorded how he would often stand on a piece of high ground, keeping other officers literally at six yards' distance, subjecting his subordinates to harsh criticism and making all decisions autocratically himself, behaviour consistent with his later conduct as a political leader. Jean Lacouture points out that for all his undoubted energy and physical courage there is no evidence in his brief period of command that he possessed the "hunter's eye" of the great battlefield commander, and that not a single one of his officers joined him in London, although some joined the Resistance in France.

De Gaulle's rank of brigadier-general became effective on 1 June 1940. That day he was in Paris. After a visit to his tailor to be fitted for his general's uniform, he visited Reynaud, who appears to have offered him a government job for the first time, and later afterwards the commander-in-chief Maxime Weygand, who congratulated him on saving France's honour and asked him for his advice. On 2 June he sent a memo to Weygand vainly urging that the French armoured divisions be consolidated from four weak divisions into three stronger ones and concentrated into an armoured corps under his command. He made the same suggestion to Reynaud.

Government minister On 5 June, the day the Germans began the second phase of their offensive (Fall Rot), Prime Minister Paul Reynaud appointed de Gaulle a government minister, as Under-Secretary of State for National Defence and War, with particular responsibility for coordination with the British. Weygand objected to the appointment, thinking him "a mere child". Pétain (Deputy Prime Minister) was also displeased at his appointment and told Reynaud the story of the ghost-writing of Le Soldat. His appointment received a good deal of press attention, both in France and in the UK. He asked for an English-speaking aide and Geoffroy Chodron de Courcel was given the job.

On 8 June, de Gaulle visited Weygand, who believed it was "the end" and that after France was defeated Britain would also soon sue for peace. He hoped that after an armistice the Germans would allow him to retain enough of a French Army to "maintain order" in France. He gave a "despairing laugh" when de Gaulle suggested fighting on.

On 9 June, de Gaulle flew to London and met British Prime Minister Winston Churchill for the first time. It was thought that half a million men could be evacuated to French North Africa, provided the British and French navies and air forces coordinated their efforts. Either at this meeting or on 16 June, he urged Churchill in vain to throw more Royal Air Force (RAF) aircraft into the Battle of France, but conceded there and then that Churchill was right to refuse.

In his memoirs, de Gaulle mentioned his support for the proposal to continue the war from French North Africa, but at the time he was more in favour of the plan to form a "redoubt" in Brittany than he later admitted.

Italy entered the war on 10 June. That day de Gaulle was present at two meetings with Weygand (he only mentions one in his memoirs), one at the defence committee and a second where Weygand barged into Reynaud's office and demanded an armistice. When Weygand asked de Gaulle, who wanted to carry on fighting, if he had "anything to suggest", de Gaulle replied that it was the government's job to give orders, not to make suggestions. De Gaulle wanted Paris to be stubbornly defended by de Lattre, but instead it was declared an open city. At around 23:00 Reynaud and de Gaulle left Paris for Tours; the rest of the government left Paris on 11 June.

Briare and Tours On 11 June, de Gaulle drove to Arcis-sur-Aube and offered General Charles Huntziger (Commander of the Central Army Group) Weygand's job as Commander-in-Chief. Huntziger accepted in principle (although according to Henri Massis he was merely amused at the prospect of forming a Breton redoubt – Huntziger would sign the armistice on behalf of Pétain a few weeks later) but de Gaulle was unable to persuade Reynaud to sack Weygand.

Later, on 11 June, de Gaulle attended the meeting of the Anglo-French Supreme War Council at the Chateau du Muguet at Briare. The British were represented by Churchill, Anthony Eden, General John Dill (Chief of the Imperial General Staff), General Hastings Ismay and Edward Spears, and the French by Reynaud, Pétain, Weygand, and Georges. Churchill demanded that the French take to guerrilla warfare, and reminded Pétain of how he had come to the aid of the British with forty French divisions in March 1918, receiving a dusty answer in each case. De Gaulle's fighting spirit made a strong impression on the British. At the meeting de Gaulle met Pétain for the first time in two years. Pétain noted his recent promotion to general, adding that he did not congratulate him, as ranks were of no use in defeat. When de Gaulle protested that Pétain himself had been promoted to brigadier-general and division commander at the Battle of the Marne in 1914, he replied that there was "no comparison" with the present situation. De Gaulle later conceded that Pétain was right about that much at least. De Gaulle missed the second day of the conference as he was in Rennes for a meeting (not mentioned in his memoirs) to discuss the plans for the Breton redoubt with General René Altmayer. He then returned to attend a cabinet meeting, at which it was clear that there was a growing movement for an armistice, and which decided that the government should move to Bordeaux rather than de Gaulle's preference for Quimper in Brittany.

On 13 June, de Gaulle attended another Anglo-French conference at Tours with Churchill, Lord Halifax, Lord Beaverbrook, Spears, Ismay, and Alexander Cadogan. This time few other major French figures were present apart from Reynaud and Baudoin. He was an hour late, and his account is not reliable. Reynaud demanded that France be released from the agreement which he had made with Prime Minister Neville Chamberlain in March 1940, so that France could seek an armistice. De Gaulle wrote that Churchill was sympathetic to France seeking an armistice, provided that an agreement was reached about what was to happen to the French fleet. This claim was later made by apologists for the Vichy Regime, e.g., General Georges, who claimed that Churchill had supported the armistice as a means of keeping the Germans out of French North Africa. However, is not supported by other eyewitnesses (Churchill himself, Roland de Margerie, Spears) who agree that Churchill said that he "understood" the French action but that he did not agree with it. He murmured at de Gaulle that he was "l'homme du destin (the man of destiny)", although it is unclear whether de Gaulle actually heard him. At the cabinet meeting that evening Pétain strongly supported Weygand's demand for an armistice, and said that he himself would remain in France to share the suffering of the French people and to begin the national rebirth. De Gaulle was dissuaded from resigning by the Interior Minister Georges Mandel, who argued that the war was only just beginning, and that de Gaulle needed to keep his reputation unsullied.

Franco-British Union