Royal survivor from world of Churchill, Truman and Stalin On the morning of 6 February 1952, 25-year-old Princess Elizabeth woke early, having spent the night with her dashing husband Philip on a treetop platform at a Kenyan game lodge. They were guarded by a white hunter who was concerned about the threat of leopard rather than paparazzi. Before breakfast she took some cine-film of rhino. She was said to be blissfully happy. It was hours before she found out she was no longer Princess Elizabeth. Communications with up-country Kenya were difficult in those days and, in any case, a cock-up was made with the code book at Government House, Nairobi. FROM Matthew Engel Eventually, Philip took the phone call. He gently gave her the news that her father, King George VI, had died in the night, aged just 56. She was now Queen. By the time they were able to get back to London, the Accession Council had met and proclaimed her sovereign. This body comprised lords spiritual and temporal, members of the Privy Council, representatives of the Commonwealth and "other principal gentlemen of quality." And, if you want to sum up in a nutshell the way Britain has changed in the past 60 years, the fact that those last five words could be used without everyone bursting into giggles pretty much tells the story. Elizabeth became Queen in a world still recovering from war, dominated by Stalin, Harry Truman and Churchill. The most intractable crisis was the Korean War. In Britain, sugar, sweets, meat and newsprint were still rationed. And though almost everything else has changed in those 60 years, there she has always been: the best-known woman in the world and yet so inscrutable she is hardly known at all. Normally, she spends February 6, a sombre day for her personally, very quietly. The official 2012 celebrations are being delayed until June. However, for what is technically her diamond jubilee, she will be venturing out from her country home at Sandringham to visit a nearby nursery school and receive a loyal address at King's Lynn town hall. She is nearly 86 now. The underlying fact about her reign has been the constitution: hers, not ours. The British constitution, notoriously, is whatever the prime minister can get away with saying it is. But her own has outclassed that of any ox - up and down the country, round and round the world, year after year, decade after decade. A word out of place? Hard to think of one. That's her husband's speciality. A foot wrong? She had a rocky week when Princess Diana died 15 years ago. Other than that . . . nothing rushes to mind. On the face of it, this is an unremarkable woman with few obvious accomplishments: Most Tribal Dances Watched by a Single Human Being; a considerable knowledge of the intricacies of breeding racehorses; a matchless gift, even by British standards, for masking her true feelings. But her very longevity in her role is an incredible achievement. Sure, the monarchy offers bonuses beyond a banker's wildest dreams. But most of us would rapidly run out screaming, as Diana did. Are there precedents? She has surpassed Henry III (1216-1272) and Edward III (1327-1377) but is not due to overtake Queen Victoria's all-time British endurance record until 2015. Yet Victoria largely locked herself away after her husband died in 1861. No nurseries in Norfolk for her in old age. Even if she matches her mother and lives to be 101, the present Queen will not quite match Sobhuza II of the Swazis, who reigned from infancy in 1899 until his death in 1982. However, after Swaziland became independent in 1968, he responded to a disagreeable election result by abrogating the constitution and ruling by decree. Elizabeth II has always resisted that temptation. For someone who has had to oversee 60 years" worth of British politicians, that's an achievement too.