On 18 June 1940, General de Gaulle broadcast from London calling on all Frenchmen to refuse to accept that the loss of the Battle of France, and the Armistice being negotiated with Germany, meant the end of the war. Britain had not been defeated and, backed by the industrial might of the USA, would continue the war. He invited all Frenchmen now in England to join him and form “La France Libre”.

Very few people in France heard the broadcast, which was transmitted by the BBC. Rather more heard a second one four days later, and soon posters appeared in London declaring that France had lost a battle, but not the war.

Few people outside military circles had heard of de Gaulle. He was only a one-star general who, for the previous couple of weeks, had been an under-secretary in the War ministry. Germaine Tillion, who worked at the Musee de l’Homme in Paris and would go on to become a member of the Resistance Group formed there that autumn, had heard one of these broadcasts and asked a general (or perhaps colonel) of her acquaintance who this de Gaulle was. She was told he was mad.

His appeal was rejected even by the vast majority of French troops, who had been evacuated from Dunkirk and were awaiting repatriation. Only 7,000 volunteered to join him. One can’t blame them. There was no great confidence of victory in Britain that summer .

De Gaulle’s position was lonely. It was also anomalous. There were governments-in-exile in London, but his was not one of them. We still recognised the French Government that had removed to Vichy as legitimate. So did several other states, including the USA, which would regard the octogenarian Marshal Petain as Head of the French State and kept its ambassador in Vichy as late as November 1942. So much for de Gaulle’s 1944 assertion that “Vichy had always been null and void”.

De Gaulle had two great qualities: self-belief and intelligence. It would be a long war but, as he explained to an aide in late August 1940, the outcome was certain. Hitler would not be able to invade England. If that had been possible he would be here already. He would not, however, resist the temptation to break his Pact with Stalin and invade Russia. At some point the Americans would enter the war. The balance was tilted against Germany; it’s defeat was assured. The important question was not who would win; it was how France would emerge from the war.

He was to prove an awkward and often exasperating ally for Churchill. This was partly a matter of temperament. It was also a matter of policy. He could not be seen in France to be an English stooge. Since the war was going to be won, he must establish France as one of the victorious powers. That required him to assert his independence.

He had a poor hand in the poker game and had to take tricks by bluffing. There was bitterness. He had to accept, and even defend on French broadcast, the British destruction of the French fleet at Oran.  Roosevelt, who retained an admiration for Marshal Petain, disliked and distrusted de Gaulle. At his insistence, de Gaulle was not told of the planned American invasion of French Algeria in November 1942. De Gaulle’s first reaction was angry: “I hope Vichy throws them back into the sea”. It took a somewhat tense lunch with Churchill and Anthony Eden to calm him down.

November and December 1942 were crucial months for de Gaulle. In Vichy, some urged the Marshal to fly to Algiers, as the Germans were about to invade the Free Zone and reduce Vichy to puppet status. He refused, saying he had promised the French people he would not abandon them.

Much later de Gaulle was asked what would have happened if the Marshal had done as urged. “The French there,” he said “ would have been delighted, the Americans would have received him with open arms, the British would have fallen into line, he would have returned to Paris on a white horse, and we, my friends, we would have been f***d”.

From then on he played his cards in masterful fashion. He outsmarted General Giraud, the American candidate for leadership of what was now La France Combattante, established some control over the internal Resistance, set up a Provisional French Government in North Africa, and though denied a role in the D-Day landings, he managed to ensure Paris was officially liberated by General Leclerc’s French forces. He himself became the symbol of Liberation with the famous march along the Champs Elysees to the Arc de Triomphe. He had come a long way from the 10 of June 1940.

Now the Fifth Republic, which he created after his return to power in 1958 when there was danger of civil war over the question of French Algeria, is sixty years old. President Macron is in London today to commemorate his broadcast of 10 June seventy years ago, and in memory of 1940, of British defiance of Nazi Germany and support of the Free French, and to confer the Legion d’Honneur on London.

Macron himself is post-Gaullist; he was born only in 1977, seven years after the General’s death. But his visit, in this time of Brexit, is an important piece of symbolism: a reminder of how throughout European history our countries have been joined together, sometimes in enmity, sometimes in friendship. One pictures de Gaulle at Churchill’s funeral, the most eye-catching of all that day, an unforgettable figure. Churchill and de Gaulle: the two men who preserved their country’s honour.