"This royal throne of kings, this scepter'd isle,
This earth of majesty, this seat of Mars,
This other Eden, demi-paradise,
This fortress built by Nature for herself
Against infection and the hand of war,
This happy breed of men, this little world,
This precious stone set in the silver sea,
Which serves it in the office of a wall,
Or as a moat defensive to a house,
Against the envy of less happier lands,
This blessed plot, this earth, this realm, this England,
This nurse, this teeming womb of royal kings,
Fear'd by their breed and famous by their birth,
Renowned for their deeds as far from home,
For Christian service and true chivalry,
As is the sepulchre in stubborn Jewry,
Of the world's ransom, blessed Mary's Son,
This land of such dear souls, this dear dear land,
Dear for her reputation through the world,
Is now leased out, I die pronouncing it,
Like to a tenement or pelting farm:
England, bound in with the triumphant sea
Whose rocky shore beats back the envious siege
Of watery Neptune, is now bound in with shame,
With inky blots and rotten parchment bonds:
That England, that was wont to conquer others,
Hath made a shameful conquest of itself.
Ah, would the scandal vanish with my life,
How happy then were my ensuing death!"
as spoken by John of Gaunt in Richard II
Strictly speaking, the philosophy of nationalism does not take root until the late 18th century. Prior to that, residents of geographical regions certainly identified with their birthplaces. In addition to the above example, written circa 1595, Shakespeare is filled with the discussion of national identities, notably the discussions about Ireland and then later, Wales, in Henry V. Certainly the rest of France looked down upon the Gascons, Prussians viewed the Poles with considerable distaste, Russians and Kievans observed each other with less than perfect respect and the Milanese did not identify with the Napolese.
But nationalism, or the civic identity that individuals possessed with relation to the government in charge of a country, that is another matter entirely. A Gascon did not cease to be a Gascon whether the region were managed by the English or the French. A Pomeranian did not modify his or her identity with the land when it came under the management of the Teutons, Swedes, Brandenburgers or Prussians. A Lith was always a Lith, a Tuscan was always a Tuscan and a Cretan always a Cretan. The occupation of the Middle East by the Ottoman Turks did not make everyone in the empire a Turk, nor was there any rhetoric demanding that a viewpoint of that nature should be adopted.
But with the push for reunifying of Germany and Italy began in the 18th century, there was a call that all 'Germans,' whether they be Saxons, Westphalians, Bavarians or Swabians, identify themselves as German; just as Friulians, Sardinians, Romans and Sicilians should suddenly identify themselves as Italians. On some level, the general ethnic identity had always been there, or else such rhetoric would never have succeeded, but in the 17th century it was but an afterthought - in the manner of Americans recognizing that they are part of the Western world, but hardly thinking that meant they should unify with France and Spain in a struggle against the Orient.
The average individual from the standpoint of Medieval 'nationalism' had little or no concern for the dealings of the European powers - and beyond taxes were rarely harassed into personal involvement. During the Crusades, while the King of France and the King of England might decide to foray into the Holy Land, they took with them only their personal retainers and hirelings. They did not conscript persons from throughout the kingdom and force them to join. The baron of a particular fiefdom in central England was not required to join along with the king on the king's insane foreign mission - in fact, the Magna Carta stated quite clearly that he was independent of the king on such matters. The various serfs and freeholders under that particular baron were therefore exempt as well. They would not have seen Richard's adventure as something that mattered to them, or even as something that mattered to England. It mattered to Richard, certainly, and Richard was to some degree synonomous with England, but that was as far as it went.
Steeped in the nationalistic philosophy as we are, and being raised on it from the age of being little children, it is virtually impossible for us to comprehend a mindset which would enable individuals to care nothing for the governmental decisions made by people ostensibly in control of the government. It is a little bit like people who speak of 'saving the Earth' in terms of environmentalism. The Earth, obviously, has little or no concern for the death of every creature on it, the removal of its atmosphere or any process that destroy most of the species on the planet - or indeed life altogether. The Earth is a large impersonal ball of stone and liquid metal that will exist as it is regardless of what happens to us. The ordinary medieval person would have viewed the Holy Land or Europe or the whole world in a similar manner ... that it did not matter what the petty creatures hacking and burning cities did, the Holy Land would remain the Holy Land because that is what it was. It did not require an act of government to declare it so.
How different is that from our own perception, in which America or Canada or the state of Russia exists because a mandate from the people has declared it to be so. In America in particular there is a real sense that without the paper, and without the laws incorporating the nation, America would somehow cease to exist. The land itself is almost meaningless. By virtue of the document, if every person in the whole world were somehow conquered or persuaded to join together under the one universal flag of the American state, the American states in Africa and Asia and so on would somehow still be identified thusly, as Puerto Rico, Guam and every base under military jurisdiction is at the present time.
This dichotomy in our perception causes us to redefine the ancient past as though those people thought as we think. Spartacus gives speeches that only an American would give, Nicholas Cage speaks absurd lines defending civil rights in Medieval Europe, King Arthur defends his people as only a 20th century politician would and so on and so forth. Meanwhile, every attempt to create a film that depicts matters as they actually were is vilified and despised, unless somehow the work is twisted at the end to emphasize how much closer the characters have grown towards the modern ideal.
Power in the present world depends upon nationalistic philosophy, to motivate its citizens towards being good taxpayers and global conflict participators, so it's only natural that any other depiction of morality and correct behavior be firmly stamped out. How interesting it is that D&D and every fantasy game predates questions like sexism, racism, freedom or Victorian morality, and yet these concepts are so firmly fought over and debated among D&D players as things that ought to matter even when they never could have. And how interesting it is that D&D also predates the formulation of most governments, or dispenses with Earthly comparisons altogether, as though somehow the fantasy world we would like to invest ourselves in doesn't have an American or a European philosophy that insists we view this or that in any particular way. The replacement of the negro with the orc allows the comfortable butchery of non-humans in a world where genocide needs not be a matter for discussion. The replacement of the old European inflexible class structure can be replaced with something allowing for personal mobility in the character-reaching-name-level framework that gets rid of bloodlines and so on that would stand in the way of players becoming the kings of countries.
It does not take long to realize that the changeover in fantasy is not so much the pursuit of a medieval world, but rather the pursuit of a mocked-up existence in which one's life isn't impressed upon by a lot of things that we're not all that fond of. Fantasy suggests a perfect world, and a perfect world does not include inconveniences such as rape, racism and genocide. After all, this is why the world did modernize, that governments could take steps to steadily get in hand the unrestrained butchery of tax-paying inhabitants. Nationalism was born from the coffers, and the coffers are not filled by roaming, irresponsible louts tearing down all that money has built. Better to take the louts and make them citizens, organize them and direct them at other louts in other nations, so that the coffers held by others can be directed into our nation's pockets.
That is, after all, nationalism. It is a strong sense that the individual's desire for personal importance is subjugated to the general welfare - the general good of all the people. We live and work by this policy continuously in our society, right down to the fellow at the D&D table who is making it hard for everyone to have a good time. We don't want to sacrifice this 'forward' thinking just for the sake of playing in a medieval world. Let the world bend to our philosophy, and not our philosophy to the world.
The appreciation of reality has its limitations, after all.