The problem is that the word “country” can have more than one meaning. It may mean a sovereign state as distinct from a colony or territory. Equally, it may mean an area of land which can be disrtinguished in some way from neighbouring areas, even though it isn’t independent.
The United Kingdom is a “country” in the sense of being a generally recognized sovereign state with a head of state, national government, army, navy, diplomatic corps, seat at the United Nations and so on.
Like many countries or nation-states, it has been formed over the centuries by the amalgamation of formerly separate territories. England and Scotland were kingdoms in their own right until 1707 (although the same succession of monarchs ruled over both from 1603). In that year, Acts of Union passed by the parliaments of both countries became law and the two kingdoms were united under the name of Great Britain. Consequently, the English and Scots naturally regard England and Scotland as “countries,” even though they have been subsumed into a larger “country.” Scotland still maintains a separate legal and judicial system from England, though of course many Acts of Parliament apply equally in both countries. Education has also always been legislated for separately in both countries.
Similarly, Wales is generally regarded as a “country,” and is often described as a principality because it usually has a Prince in the person of the eldest son of the reigning monarch. The English spent three or four centuries trying to take over Wales: it was finally officially subsumed into England in the 1530s under Henry VIII. From then until recently there was little or no official recognition of separateness: official statistics and regulations lumped Wales together with England. However, the Welsh preserved their national culture and language pretty well, and so it has always seemed natural enough to regard Wales as a “country.”
For the last few years Scotland and Wales have had a greater degree of independence from the UK’s central government. Scotland has its own Parliament and Wales has its Assembly, with a degree of freedom to legislate for their own countries in certain matters.
I’m not sure whether there’s a word that really characterizes the status of Northern Ireland. It’s difficult to see it as a country in the same way as England, Wales or Scotland. It’s sometimes called a “province,” but that’s a word that has no administrative meaning in the UK; and the ancient Irish province of Ulster included three counties in the Irish Republic as well as the six counties of Northern Ireland. Discussion of this question in depth is impossible without taking account of Anglo-Irish relations over eight centuries, and that would be likely to turn the discussion into a “Controversial Issue”!
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