The story
- Proto-Turkic*bulga-
- Proto-Turkic*bulgar
- Old Turkic𐰉𐰆𐰞𐰍𐰀 (b¹wl¹g¹a)
- Old Church Slavonicблъгаринъ (blŭgarinŭ)
- Medieval LatinBulgarus
- EnglishBulgar
- English todayBulgaria
From Medieval Latin Bulgaria, equivalent to Bulgar + -ia, in English used from the 16th century.
Etymology from Wiktionary, CC BY-SA 4.0.