Book excerpt: We can hardly imagine a Britain without Elizabeth II on the throne. It seems to be the job she was born for. And yet for much of her early life the young princess did not know the role that her future would hold. She was our accidental Queen.Elizabeth's determination to share in the struggles of her people marked her out from a young age. Her father initially refused to let her volunteer as a nurse during the Blitz, but relented when she was 18 and allowed her to work as a mechanic and truck driver for the Women's Auxiliary Territorial Service. It was her forward-thinking approach that ensured that her coronation was televised, against the advice of politicians at the time.Kate Williams reveals how the 25-year-old young queen carved out a lasting role for herself amid the changes of the 20th century. Her monarchy would be a very different one to that of her parents and grandparents, and its continuing popularity in the 21st century owes much to the intelligence and elusive personality of this remarkable woman.