Identifying the Relevant English Suffixes
First, let’s consider the English suffixes that are most commonly used to create adjectival forms of country names, and the situations in which they arise. The following distinctive forms struck me as being especially prevalent: -ian as an adjectival suffix in situations where the country name ends in -ia; -ian as an adjectival suffix in situations where the country name does not end in –ia; -n as an adjectival suffix in situations where the country name ends in -a (but not in -ia); -an as an adjectival suffix for country names not ending in -a; -ese as an adjectival suffix; -i as an adjectival suffix; -ic as an adjectival suffix; -ish as an adjectival suffix in situations where the country name ends in -land; -ish as an adjectival suffix in situations where the country name ends in something other than -land; and situations where the adjectival form of the country name is a truncation of the country name. There are also some special cases that don’t follow any recognizable pattern.
Various reference works have analyzed the suffixes involved. Here is what Michael Quinion, Ologies and Isms: Word Beginnings and Endings (2002) has to say about each of the relevant suffixes:
-ese Forming adjectives and nouns. [Old French -eis, based on Latin -ensis.]
Adjectives denote an inhabitant or language of a city or country: Cantonese, Japanese, Maltese, Nepalese, Taiwanese, Vietnamese, Viennese.
...
-i Adjectives and nouns relating to countries [Semitic and Indo-Iranian adjectival endings.]
The countries are in the Near or Middle East or South Asia, and the forms can either be adjectives relating to the country, or nouns for a native or national of the country: Azeri, Azerbaijani, Bangladeshi, Hindi, Israeli, Kuwaiti, Nepali, Pakistani.
...
-ian Also -an. Forming adjectives and nouns. [Latin adjectival endings -anus, -ana, -anum, ‘of or belonging to something’.]
The original form was -an, as in urban [etymology omitted] and Roman [etymology omitted]. However, many Latin words had an i before the ending [example omitted] and other examples ending in -ian come from French words ending in -ien [example omitted] that are derived from Latin. As a result, the usual form is now -ian, though it is truncated to -an if the stem ends in a vowel.
One set is of adjectives that refer to places: Australian, Chicagoan, Indian, Kenyan, Malayan, Nebraskan, Parisian, Puerto Rican, Scandinavian, Tibetan, and so on. Some modify the stem: Glaswegian, Norwegian, Peruvian. Most can also be nouns that identify a person from the place.
...
-ic Forming adjectives and some nouns. [French -ique, Latin -icus, or Greek -ikos.]
...
-ish Forming adjectives. [Old English -isc, of Germanic origin; related to Old Norse -iskr, German and Dutch -isch, also to Greek -iskos (a suffix forming diminutive nouns).]
This suffix forms adjectives from nouns and from other adjectives.
One set from nouns is of adjectives for a member of a nation (British, Cornish, Irish, Netherlandish, Polish, Swedish, Turkish), occasionally of a religious or other group, as with Jewish. Rarely, the ending has been reduced to -sh, as in Welsh.
To sum up, the sources of the suffixes used to create the adjectival forms of most country names in English are Old French (-ese), Semitic and Indo-Iranian (-i), Latin (-ian and -an), French (-ic), and Old English (-ish). That’s quite a smorgasbord.
Sorting the Adjectives into Nonoverlapping Categories
Before doing any research into the relevant suffixes, I tried to sort a bunch of adjectives (172 of them, altogether) derived from past or current country, continent, or region names into coherent categories. I ended up with ten distinct categories, plus one catch-all category for unique oddball adjectives. (Note that the adjectival forms given here are descriptive adjectives for the place, which may not match the word used for the people or language associated with the place name.)
Place names ending in -ia that take the adjectival form -ian (40):
Albania, Albanian; Algeria, Algerian; Arabia, Arabian [or Arab or Arabic]; Armenia, Armenian; Austria, Austrian; Australia, Australian; Asia, Asian; Bolivia, Bolivian; Bosnia, Bosnian; Bulgaria, Bulgarian [or Bulgar]; Cambodia, Cambodian; Catalonia, Catalonian [or Catalan]; Colombia, Colombian; Czechoslovakia, Czechoslovakian [or Czech]; Croatia, Croatian; Estonia, Estonian; Ethiopia, Ethiopia; Georgia, Georgian; India, Indian; Indonesia, Indonesian; Latvia, Latvian; Liberia, Liberian; Lithuania, Lithuanian; Macedonia, Macedonian; Malaysia, Malaysian; Mauritania, Mauritanian; Mongolia, Mongolian; Namibia, Namibian; Nigeria, Nigerian; Prussia, Prussian; Romania, Romanian; Russia, Russian; Serbia, Serbian
Slovakia, Slovakian; Slovenia, Slovenian; Somalia, Somalian [or Somali]; Syria, Syrian; Tanzania, Tanzanian; Tunisia, Tunisian; Zambia, Zambian
Place names ending in something other than -ia but taking the adjectival form -ian, sometimes with additional alterations (26):
Alsace, Alsatian; Argentina, Argentinian [or Argentine]; Babylon, Babylonian; Bahamas, Bahamian; Belgium, Belgian; Brazil, Brazilian; Burgundy, Burgundian; Cameroon, Cameroonian; Canada, Canadian; Chad, Chadian; Ecuador, Ecuadorian; Egypt, Egyptian; Ghana, Ghanaian [or Ghanian or Ghanese]; Herzegovina, Herzegovinian; Hungary, Hungarian; Iran, Iranian; Italy, Italian; Ivory Coast, Ivorian
Jordan, Jordanian; Laos, Laotian [or Lao]; Luxembourg, Luxembourgian; Norway, Norwegian; Palestine, Palestinian; Peru, Peruvian; Sicily, Sicilian; Ukraine, Ukrainian
Place names ending in -a (but not in -ia) that take the suffix -n (21):
Africa, African; America, American; Angola, Angolan; Botswana, Botswanan; Costa Rica, Costa Rican; Cuba, Cuban; Dahomey, Dahomeyan; Eritrea, Eritrean; Guatemala, Guatemalan; Guinea, Guinean; Jamaica, Jamaican; Kenya, Kenyan; Korea, Korean; Libya, Libyan; Moldova, Moldovan; Rwanda, Rwandan [or Rwandese]; Sahara, Saharan; Sri Lanka, Sri Lankan; Uganda, Ugandan; Upper Volta, Upper Voltan; Venezuela, Venezuelan
Place names not ending in -a that take the suffix -an, sometimes with other alterations (21 + 1 exception):
Brunei, Bruneian; Burundi, Burundian; Chile, Chilean; Djibouti, Djiboutian; Ecuador, Ecuadoran [or Ecuadorean or Ecuadorian]; Europe, European; Haiti, Haitian; Madagascar, Madagascan; Malawi, Malawian; Mali, Malian; Mexico, Mexican; Morocco, Moroccan; Mozambique, Mozambican; Paraguay, Paraguayan; Puerto Rico, Puerto Rican; Sierra Leone, Sierra Leonean; Singapore, Singaporean; Tibet, Tibetan; Uruguay, Uruguayan; Zaire, Zairean [or Zairian]; Zimbabwe, Zimbabwean
[Exception: Montenegro, Montenegrin]
Place names that take the suffix -ese, sometimes with other alterations (20):
Burma, Burmese; Ceylon, Ceylonese; China, Chinese; Benin, Beninese; Bhutan, Bhutanese; Congo, Congolese; Faroe Islands, Faroese; Gabon, Gabonese; Guyana, Guyanese; Japan, Japanese; Lebanon, Lebanese; Nepal, Nepalese; Portugal, Portuguese; Siam, Siamese; Senegal, Senegalese; Sudan, Sudanese; Suriname, Surinamese; Taiwan, Taiwanese; Togo, Togolese; Vietnam, Vietnamese
Place names that take the suffix -i (8):
Bangladesh, Bangladeshi; Iraq, Iraqi; Israel, Israeli; Kuwait, Kuwaiti; Oman, Omani; Pakistan, Pakistani; Qatar, Qatari; Yemen, Yemeni
Place names ending in -land that take the suffix -ish, sometimes with final consonant doubling (5):
England, English; Finland, Finnish; Ireland, Irish; Poland, Polish; Scotland, Scottish
Place names ending in -land that take the suffix -ic (2):
Greenland, Greenlandic; Iceland, Icelandic
Other place names ending in -ish, sometimes with other alterations (7):
Flanders, Flemish; Kurdistan, Kurdish; Spain, Spanish; Sweden, Swedish; Denmark, Danish; Turkey, Turkish; Wales, Welsh
Place names with truncated, and sometimes further altered,
adjectival forms (14):
Afghanistan, Afghan; Germany, German; Kazakhstan, Kazakh [or Kazakhstani]; Kyrgyzstan, Kyrgyz; Lapland, Lapp; Myanmar, Myanma; Netherlands, Netherland [or Netherlandic or Netherlandish]; Philippines, Philippine; Saxony, Saxon; Switzerland, Swiss; Tajikistan, Tajik; Thailand, Thai; Turkmenistan, Turkmen [or Turkmenian]; Uzbekistan, Uzbek [or Uzbeki or Uzbekistani]
Special cases (7):
Burkina Faso, Burkinabe; France, French; Cyprus, Cypriot; Greece, Greek; Isle of Mann, Manx; Niger, Nigerois; Holland, Dutch
Assessing the Results
When you look at the entries closely, you quickly see that even some members of a relatively well-ordered group may be unpredictable. For example, according to Quinion, the -an family consists of adjectives whose -ian ending is “truncated to -an [because] the stem ends in a vowel.” But how then do we explain Ecuadoran, Madagascan, and Tibetan? And why is the adjectival form of Montenegro (in Merriam-Webster, anyway) Montenegrin instead of Montenegran?
Likewise I can’t see any compelling reason why Africa, a three-syllable word ending in a and with the stress on the first syllable, took the adjectival form African, while Canada, a three-syllable word ending in a and with the stress on the first syllable, took the adjectival form Canadian.
For a more advanced challenge, see if you can explain why England yields English, Finland yields Finnish, Iceland yields Icelandic, Switzerland yields Swiss, and Holland yields Dutch. Given that record of inconsistency, I have no idea what the preferred adjectival form for Falkland Islands is—Falklish? Falklandic? Falk? Falklandese? The answer certainly isn’t intuitively obvious from the disparate forms that other -land-based adjectives have taken.
Another important point involves the vastly different eras when different adjectival forms were created. England’s oldest and nearest neighbors (and England itself) get the Old English–derived -ish treatment. In sharp contrast, the various Middle East and South Asian states that gained independence after World War II are the likeliest to have acquired the Semitic and Indo-Iranian suffix -i. An extreme example from the “Special cases” category is Burkinabe, the approved adjectival form of Burkina Faso, a country whose new name (supplanting Upper Volta) is itself only 30 years old. The -be suffix in Burkinabe is presumably drawn from an indigenous language, as indeed Burkina is (Faso is from the nation’s other major language, according to Wikipedia); but it’s hard to imagine the foreign office in Britain or the United States a century ago showing much solicitude for the preferences of colonial populations—their own or any other country’s—in the framing of place-name adjectives.
A further complication involves inconsistent adjective assignments through the years. In its entry for the adjective Chinese, for example, the full-size OED notes that “In 16th c., Chinish was used.”
Simple practicality explains why one member of the oddball category has an unusual suffix. Nigerois, the adjectival form of Niger, exists simply because the obvious choice, Nigerian, was already taken by Nigeria. We’re unlikely to see any other place-name adjectives with -ois endings (except perhaps Quebecois) unless a similar conflict over rights to the obvious English word arises.
Ultimately, there are far too many variations in the adjectival forms of place names with similar endings in English to permit any universal and systematic explanation for the endings actually chosen. Nevertheless certain patterns are evident in certain places or with certain endings—and most English adjectives based on country names at least have similar (and similarly derived) words to keep them company.
