A lot of confusion around Russia territory stands from the break-up from the Soviet Union and what is included and what not. Plus Russia supports a lot of smaller republics and is also the largest country in the world (considering land mass). Both Bulgaria & Russia are located in Eastern Europe and speak a common language “Slavic”.
Similarities between Bulgaria and Russia:
As mentioned above, they are located in the same region and speak a similar language. But their relations go deeper than this. During the Russo-Turkish war of 1877-1878, the Third Bulgarian Tsardom defeated the Turks and liberated Bulgaria. So it was Russia intervention that helped Bulgaria gain independence from the Ottoman Empire.
Since then many have suggested that Bulgaria is a puppet state and that was true after the Second World War. As Bulgaria was under a de-facto Soviet control during the cold war. Due to which many older Bulgarians also speak Russian.
But after the Soviet Union splits, relations have whittled a bit and the only similarity is both countries follow the Eastern Orthodox Christian faith.
Is Bulgaria a part of Russia?
The simple answer to this is no, Bulgaria isn’t a part of Russia and never was. The black sea distinctly separates both Russia and Bulgaria. Although both countries speak the same language of Slavic, their accent is quite different same as to an Irish or a wales men to an Englishman.
Bulgaria is very different to Russia in its mentality as well. Russia is known to big empty cold place with a lot of harsh people around. Bulgaria isn’t like that, it is certainly isn’t tropical but less cold with more densely populated areas and the people are also more easy-going and chilled in compare to their neighbor.
This is because of the fact that in recent times Bulgaria has come close to the west after its inclusion in the European Union (EU), making them more open to freedom of speech, trade, foreign ideas, contact, languages, etc.
Bulgaria & Russia relations today:
Both the countries have friendly relations as Russia hasn’t invaded them yet. Though Bulgaria is a part of the EU, NATO, and a strong strategic ally to the USA. But the shared culture, history, language, and business relations make both the country close. That’s the only obstacle between Bulgaria joining the status quo of “Western Culture”.