Recent country names are carried across from whatever the country is calling itself, without much alteration: Bhutan, Nepal, Senegal, Angola.
Neighbouring countries that England had close contact with traditionally would have the most diverse names—mainly based on what those countries called themselves, but looking Germanic, and not made to be consistent. Scotland, Ireland, Denmark, Wales, France, Flanders, Norway, Sweden.
Otherwise, the main source of country names for the “Old” World—Europe, North Africa, major countries of Asia—is Latin, and indirectly Greek, as the prestige languages of English learning for a very long time. Thence the –ia suffix, which actually goes through three iterations:
–ia for more recent loans, straight out of Latin, and less familiar countries (Albania, Persia, India, Slovakia)
–y for Middle English and Early Modern English (from French), many instances of which later went to –ia (Turkey, Hungary, Italy; Normandy, Picardy; Indies for India, Candy for Candia = Crete)
–e or nothing for very old and familiar country names (France, Spain)
I’m not necessarily the best person to be answering this: I lived in Greece in the 80s, before the thawing in relations between Greeks and Turks in the ’90s. So my answers will err on the out-of-date side.
The folk song published by Nikolaos Politis in 1914 about the capture of Haghia Sophia was everywhere in the Greek education system. (I don’t know if it still is.) And it is an astonishing poem—
God sounds; the earth sounds; and the heavens sound; Haghia Sophia sounds, that mighty church, with two-and-sixty bells, four hundred woodblocks
—even if it’s a pastiche of a couple of dozen actual folk songs. It was all the more popular in Greece because of its ending:
“Quiet, Our Lady Mary, cry not so! When times have passed, it will be ours once more.”
But Greeks can feel that Constantinople is theirs, without going further and saying that it is theirs alone, that they want to drive the Turks out, that they want to push the Greek borders to the Bosphorus. Greeks—and not just Neonazis—are funny to this day about calling the place Istanbul. (The Rum who actually live there are rather more sanguine about it—which offends Greeks.) Constantinople was the centre of Greek culture from 330 AD to well past the establishment of Athens as the capital of Modern Greece in 1833. That’s one and a half millennia of history. And Greeks care about their history, even when it isn’t Classical.
I became infatuated with this folk music show episode that Dimitra Triantafyllidou shared with me. It features the music of Istanbul. It is anti-nationalist to an extent that nauseates YouTube commenters. It takes pain to refer to Rum musicians in Istanbul, not Greek. It takes pains to say that the music of Istanbul was not Greek or Turkish or Jewish or Armenian but Istanbullu. The fiddler Sokratis Sinopoulos has made himself an expert on Ottoman art music, and speaks of the Turkish musician Derya Türkan as his brother.
But for all that, they don’t say Istanbullu in the episode. They say Politiko. And the ethnomusicologist host Lambros Liavas signs off the episode with this:
“Thank you for accompanying us on this beautiful voyage to the City of our hearts, the City of Constantinople. The City is always there, to grant the joy of human expression to all peoples, regardless of religion, language, or ethnicity.”
—before joining in the dance himself.
Do modern Greek people feel that Istanbul/Constantinople belongs to them? In a territorial sense, no. In a nationalist sense, no, outside of a lunatic fringe. In a daily life sense? Like both Vasilis Sekal and Electra K. Vasileiadou said: when you actually go there as a Greek, you realise that 18 million people go about their daily traffic jams and hang out in Üsküdar cafes and protest in Taksim Square, without any notion of belonging to Greece. It will not, once more, be ours.
Is there a Greek emotional attachment to Constantinople? Of course. It will still be ours. That won’t change in a hurry. And as I’d like to think people like Sinopoulos and Liavas show, that’s not a bad thing.