The United Kingdom of Great Britain and Northern Ireland is a country composed by four nations: England, Wales, Scotland and Northern Ireland. The UK is the metropoli of the British Empire and the leading nation in the British Commonwealth.
From 1939, when Germany invaded Poland, to 1986, when the National-Socialist regime in Germany fell, Britain and her allies were the main contender against Germany and the Axis. Britain managed to preserve the situation of arbitrator of Europe during the Second Great War, contending Germany during the early expansion, overturning the Soviet Union and managing to preserve liberal principles over national-socialism all over the world.
During the process, the British Empire became Britain main asset. The British Empire evolved from a colonial empire into a commonwealth. While some colonies were integrated to the kingdom, other were granted an independence status into a commonwealth of equals.
Britain keep the leadership in technological progress. The evolution of radio and computers, aviation and space exploration had in Britain a leading role. Germany launched the first artificial satellite in 1955, but Britain set the first man in orbit in 1958, beating again Germany in the race for the Moon (1966). The first atomic bomb was developed in Canada founded and lead by British scientist in 1948, soon followed by neutral USA (1950). Germany did not develop her own functional nuclear device before 1959. By this time, British nuclear arsenal was so impressive that the bomb was never used in a war.