Willy replied that he had gone to the utmost limits in his efforts to keep the peace; that he wouldn’t be the one to bear responsibility for the disaster now threatening the civilized world; and that if the Russian mobilization of troops was halted, a general war could still be avoided.

It was a telegram that his government followed up with an ultimatum. Unless Russia halted mobilization within twelve hours, Germany would have no alternative but to mobilize also.

When the deadline arrived and Russia had not replied, Willy carried out his threat and, as there was still no response from Nicky, on 1 August Germany declared herself to be at war with Russia.

Denmark, Sweden and Norway hurried to declare their neutrality.

France mobilized.

On 3 August, Germany declared war on France, and Belgium refused permission for German troops to pass through its country en route to France. As if he had no memory of King Albert and Queen Elisabeth sitting alongside him at Sissy and Ernst’s wedding breakfast in close family harmony, Willy signed an order that sent his troops marching through Belgium anyway.

It was too much for the British government. On 4 August, George signed the document declaring that Great Britain and all her Dominions over the seas were now at war with Germany.

When they were alone together, George said, ashen-faced, ‘There was no alternative, May. Belgium is a neutral country, and for Willy to have ignored that . . .’ His voice shook. ‘We had to come to King Albert’s aid, but that it should have come to this, May.’ Tears streamed down his face. ‘War with Germany. What on earth would Granny Queen have said?’

Knowing the kind of response he needed, she said robustly, ‘Granny Queen would have said it is none of your fault, George, and she would have been heartbroken, as we are, and as all the rest of the family are.’

An hour later she stood next to George on the balcony of Buckingham Palace, in front of a vast cheering, flag-waving crowd that stretched from the palace gates all the way down The Mall to Admiralty Arch and beyond. It was a sea of thousands, all wanting to show loyalty to her and George, and all exultant at the thought of a war that would show the bullying Germans what was what. It took all of May’s iron self-control to keep her own, very different emotions from showing.

She hadn’t been exaggerating when she had said that she was heartbroken. Only fifteen months ago, at Sissy and Ernst’s wedding, the Royal Mob had been united in close family togetherness; now it was difficult even to know on what side of the conflict some members of the family stood. For nearly all of them had either married Germans or, like herself, had far more German blood in their veins than English blood.