Count: 0 — No European countries have English short names that begin with the letter O. This list follows the A–Z rule for sovereign states and transcontinental countries with territory in Europe, and it excludes dependent territories unless they are widely treated as independent. An interesting detail: several local or historical names start with an O-like letter (for example, Austria’s German endonym is Österreich), and the only widely recognized country in English that begins with O is Oman, which is in Asia, not Europe.

Consult the UN, Eurostat, and the CIA World Factbook for authoritative country lists; none of these sources list a sovereign European state whose common English name starts with O. This absence reflects historical naming patterns and language roots across Europe: English short names for European countries derive from Latin, Germanic, Slavic, Celtic and Romance traditions that rarely produce O-initial forms, and no modern European state adopted an O-initial English short name when national names standardized.

Expect near-misses rather than true matches. Look for cities and regions that start with O (Oslo, Odesa, Orkney), local endonyms (Österreich), or dependent places and historical entities that begin with O, but treat these as distinct from sovereign states. Use the full A–Z table of countries, capitals, populations and official languages from UN, Eurostat, CIA World Factbook and national statistical offices for the complete, citable reference.