The European Community expands to include Denmark, Ireland and the UK.
Britain had faced strong opposition to its membership from French President Charles de Gaulle, who vetoed its application a decade earlier.
Britain only holds a referendum on its membership two years later in 1975 and the British public votes to stay in the EEC.
Norway had also been gearing up to join in this round of expansion, but in its referendum in 1972 Norwegians decided against membership and negotiations to join were stopped.
