Country codes in use include:
{| class="wikitable" style="text-align: left"|-|*A8 = Austria-Hungary||*AM GR = ArmeniaGreece||*B9 NO = Byzantine EmpireNorway|*BB AM = BarbadosArmenia||*BS GT = BahamasGuatemala||*C3 O8 = CarthageOttoman Empire|*CA B9 = CanadaByzantine Empire||*CH H3 = SwitzerlandHawai'i (as a nation)||*CN OM = ChinaOman|*CU BB = CubaBarbados||*DE H6 = GermayHoly Roman Empire||*DK PO = DenmarkPoland|*E6 BS = England (see also G7, UK)Bahamas||*EE HU = EstoniaHungary||*EG PT = EgyptPortugal|*EI C3 = IrelandCarthage||*ET IL = EthiopiaIsrael||*FR R6 = FranceRome|*G7 CA = Great Britain (see also E6, Canada||*IM, S3, UK, W3)= Isle of Man||*GE RU = Georgia (nation)Russia|*GR CH = GreeceSwitzerland||*GT IN = GuatemalaIndia||*H3 S3 = Hawai'iScotland|*H6 CN = Holy Roman EmpireChina||*HU IS = HungaryIceland||*IL SA = IsraelSaudi Arabia|*IM CU = Isle of ManCuba||*IN IT = IndiaItaly||*IS SY = IcelandSyria|*IT DE = ItalyGermany||*JM = Jamaica||*JO SZ = JordanSwaziland|*JP DK = JapanDenmark||*LT JO = LithuaniaJordan||*LY UK = LibyaUnited Kingdom (see also E6, G7, IM, S3, W3)|*M5 E6 = MinosEngland (see also G7, UK)||*M6 JP = MoraviaJapan||*MC US = MonacoUnited States (see also State codes)|*MX EE = MexicoEstonia||*N3 LT = NaplesLithuania||*NO VA = NorwayVatican City|*O8 EG = Ottoman EmpireEgypt||*OM LY = OmanLibya||*PO W3 = PolandWales|*PT EI = PortugalIreland||*R6 M5 = RomeMinos|||*RU ET = RussiaEthiopia||*S3 M6 = ScotlandMoravia|*SA FR = Saudi ArabiaFrance||*SY MC = SyriaMonaco|*SZ G7 = Swaziland*UK = United Kingdom Great Britain (see also E6, G7, IM, S3, UK, W3)||*MX = Mexico|*US GE = United States Georgia (see also State codesnation)||*VA N3 = Vatican CityNaples*W3 = Wales-}
Many locations have been part of different countries over the centuries. Items are shelved by the name of the ruling country at the time in question. When works cover a long period, they are shelved under the current name, or rarely under the most common one.