I declare before you all that my whole life shall be devoted to your service'

Living through extraordinary times, the Queen provided a rock of stability, sticking to fundamental principles while bringing the monarchy closer to the people. Robert Jobson on a life of celebration

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SHE lived a life of service that began long before her accession to the throne.

In 1940, at just 14 years old, the then Princess Elizabeth made her first BBC radio broadcast to bring comfort and hope to the children who had been evacuated from Britain's cities during the Second World War.

At 18 she became the first female member of the royal family to join the armed forces, enlisting with the women's Auxiliary Territorial Service, training as a driver and a mechanic.

At 21 she made that exquisite and defining broadcast from Cape Town in which she uttered those famous words, dedicating her life to the service of the Commonwealth, saying: "I declare before you all that my whole life, whether it be long or short, shall be devoted to your service." Never has such an extraordinary promise been so diligently fulfilled.

If you think of the vital landmark in completing the United Kingdom's journey to democracy when everyone over the age of 21 was finally given the vote in 1928, then it means that Her Majesty presided over two thirds of the UK's history as a full democracy.