It is not that Bulgarians don’t have a word for ‘thank you’. Their word to express gratitude is ‘blagodarya’ (pronounced blah-goh-dah-rya) and they use it along with the French, with subtle variations in meaning. If you spend a little more time in the country though, you will notice that the French equivalent can be heard very often, if not more often. In order to understand why Bulgarians use a French word for “thank you” so often, you will have to delve into a little history.
Bulgaria gained its liberty from the five-century rule of the Ottoman Empire in 1879. As a young country that had been part of an Oriental state for so long, it strived to create its independent image on the world stage and stand proud as a European country. So a strong trend of negating everything influenced by the Ottoman era, from clothing to language, swept the country. This was the time when Bulgarians started wearing European clothes (as opposed to the Oriental costumes they used to wear before), furnishing their homes with Viennese cupboards, tables, and chairs, and searching for new words to substitute the ones that existed only in Turkish in the language at that time.
One of the greatest European influences felt in the country then was the French. Many French words infiltrated the Bulgarian language, such as ‘madame’ and ‘merci’. To incorporate French words while speaking was considered a sign of a modern and progressive mind.
Later on, a desire to purify the language made linguists work on weeding out the ‘intruder’ words. Some of the foreign words were cleared out of the language, while others managed to persevere through the years, merci being among them.
According to the Bulgarian linguistic specialist Vladko Murdarov, the contemporary use of the word merci has slight differences from the Bulgarian word blagodarya. Merci is usually used when you thank for a trivial favor or something not really significant, while blagodarya comes when you are extremely thankful or someone has done you a great favor. Additionally, merci is used in informal communication and using it in a formal situation may be considered rude.