The Queen's reign began unexpectedly on an ordinary Wednesday in 1952. King George VI, The Queen's father, died suddenly at Sandringham on 6 February after several years of ill health. The news of his death reached 25-year-old Princess Elizabeth in the afternoon of that day in Kenya, where the Princess and Prince Philip had just begun a Commonwealth tour. Having left Britain a Princess, she was to return as Queen.

Upon the news of King George's death, the Royal party flew back to Britain, arriving at London Airport the next day after a 4,600 mile journey. The new Queen was met by Winston Churchill, Prime Minister, and Foreign Secretary Anthony Eden. Following the funeral of King George VI and the 16-week period of Court mourning, there was opportunity for national celebration the following year with the coronation of Queen Elizabeth II in Westminster Abbey on 2 June 1953.

From the earliest days, The Queen took up her new role with energetic commitment.
Political duties began immediately, from the State Opening of Parliament to weekly audiences with the prime minister. The first prime minister of The Queen's reign was Winston Churchill. The Queen also had occasion to exercise her Royal prerogative, appointing Harold Macmillan as prime minister in 1957. At that time, the Conservative Party did not have any formal electoral machinery to choose a new leader, and The Queen acted on the advice of government ministers. It was a duty which was to arise again in 1963.

The Queen took her role as Queen of the whole of the United Kingdom seriously. She began a wide-ranging programme of visits throughout every part of the country. Her first regional tour was a three-day visit to Northern Ireland. In the same decade The Queen travelled north, south, east and west, from Shetland to the Isles of Scilly, and from Swansea to Holy Island.

Taking up her duties as Head of the Commonwealth in earnest, The Queen embarked on a series of overseas visits, including some long tours. Within the first few years of her reign, The Queen travelled to parts of the Commonwealth never before visited by her predecessors. The Queen also represented Britain in State Visits to countries including Norway, Sweden, Portugal, France, Denmark, the USA and the Netherlands.

Family life remained an essential stay throughout official duties. As well as being Sovereign, The Queen was a mother with two young children to care for. With the birth of Prince Andrew in 1960, The Queen became the first reigning Sovereign to give birth since Queen Victoria, who had her youngest child, Princess Beatrice, in 1857.

Source info: British Royal House