Finally, on 8 May 1945, Victory in Europe day, the war in Europe was over. Princess Elizabeth and Margaret slipped out of the palace to join the crowds singing in the streets. ‘It was one of the most memorable nights of my life,’ Princess Elizabeth said later. ‘It was most exciting – we went everywhere,’ Princess Margaret recalled.

Philip was not with them, as he was still at sea onboard Whelp steaming for Tokyo Bay. He witnessed the Japanese surrender in August aboard Missouri, the flagship of the US fleet, and did not return to England until January 1946. Whelp was decommissioned before being offered to South Africa, meanwhile Prince Philip was posted as a lecturer to the officers’ training school at Corsham near Bath.

Whenever he had leave he would drive up to London in his MG sports car to stay at the Mountbattens’ house in Chester Street, Belgravia. John Dean, who later became Philip’s valet, wrote: ‘He was so considerate, so anxious to avoid giving trouble to people who, after all, were paid to look after the family, that we all thought the world of him and looked forward to his visits.’

Dean remarked that Philip did not have much in the way of civilian clothing and often did not even have a clean shirt. ‘At night, after he had gone to bed, I washed his shorts and socks and had them ready for him in the morning. I also did his mending. He was very easy to look after, and never asked for things like that to be done for him, but I liked him so much I did it anyway. Whenever Prince Philip brought a weekend bag and I unpacked it, I always found a small photograph in a battered leather frame – a photograph of Princess Elizabeth.’

Because of the rigid rules of court etiquette, apart from the odd occasion when Philip managed to synchronise his leave with invitations for the same parties as the princess, they had to be patient, which of course Philip wasn’t. He could hardly turn up at the palace without a personal invitation, and if Elizabeth invited him for a pre-dinner drink in her suite of rooms, there always had to be a chaperone in the room. Princess Margaret was often there, but demanded just as much attention from Philip as if he were her own admirer. If they got invited to the same parties, all they could hope for were a couple of dances together. If there had been more, people would have started talking even more than they already were, as rumours of the royal romance began to appear in the press, after Prince Philip and Princess Elizabeth were seen together at the theatre and dancing at nightclubs.