Here are the equivalents I have always used, which are very close to IronChef's in some respect:
Aquilonia: Latinized France.
Argos: Heroic (Homeric) Greece.
Corinthia: Classical (City-State) Greece.
Hyperborea: Finland (as inspired by the Kalevala).
Iranistan: Iran, pre-Islamic Persia with a dash of Arab culture.
Khitai: China of the Warring States period (Three Kingdoms).
Kush: An Egyptianized version of various kingdoms of the Sahel and forestlands (sub-Saharan western Africa).
Nordheim (Vanaheim/Asgard): Norway and Sweden, with the applicable mythic additions of the Vanir and Aesir.
Stygia: Egypt, classical pre-Islamic of course.
Vendhya: India, pre-Buddhist.
Zamora: A mix of the Balkans, rather than the Ukraine, specifically the Romanians and Southern Slavs.
Zingara: Spain, pre-1492.
Ophir: Northern Italian city-states (Lombardy) during the time of the mid to late Holy Roman Empire.
Nemedia: Latinized Germany of the time of the Holy Roman Empire (though rather more united than that would seem).
Brythunia: Some non-Howard Conan authors have portrayed it as Poland, others as Wales. I have my Brythunians being similar to the "modern" Bossonians and Ligureans, and thus somewhat of a Welsh/Saxon mix. My Brythunians, like the Bossonians, are a mix of the pre-Acheronian native population with the Hyborians, whereas the Aquilonians, Nemedians, and Ophireans are a mix of Acheronian/pre-Acheronian/Hyborian.
Koth: I see Koth as a mix of the Byzantine Empire, combined with the Hellenic Kingdoms and City-States of the post-Alexander period (Selucids, Ptolemies, etc.), with a very heavy admixture of Canaanite and Phoenician/Punic culture.
Khauran and Khoraja: As Koth, with heavy Canaanite influence.
Shem: The meadowlands of the west are Canaanite, the central cities are Babylonian/Sumerian, and the deserts of the east are Arabic.
Darfar: Various Nigerian tribes with a heavy pulp influence.
Keshan: Ancient Meroe (i.e., "Black Egypt").
Punt: As Keshan, with Abassynian influence.
Zembabwei: Zimbabwe of myth and legend.
Turan: Turkey of the Ottomans.
Kosala: Much like Vendhya, above, only with odd non-historical elements.
Meru: Nepal and Tibet.
Kambuja: Various cultures of Indochina, including Vietnamese, Khmer, Siam, and so forth.
Kusan: Western Chinese mountain kingdoms (the kind that were extinguished by Genghis Khan).