Since the population was 85% ethnic Bulgarians, there was relatively little social strife aside from the conflict between the haves and have-nots.
Most inhabitants of Sofia maintained close ties to the countryside, but this did not prevent a rift between the peasants and urban class (i.e. Sofia versus everyone else), although some was the result of deliberate manipulation by politicians seeking to take advantage of traditional peasant distrust of the "effeminate city slicker".
Mostly however, it was due to a quarrel between the rulers and the ruled.
Around 14% of the population were Muslims, mostly Turks (i.e. the remnant of the landowning class), but also a handful of so-called "Pomaks" (ethnic Bulgarians who practiced Islam).
The Muslim population was alienated from the dominant Orthodox Christians both due to religious and historical reasons.
They neither pressed for minority rights nor tried to set up their own schools, and instead asked nothing more than to be left alone to mind their own business.
The Bulgarian government obliged except for a great willingness to assist them in emigrating back to Turkey.

By comparison to economics, Bulgaria's educational system was highly successful and less than half the population were illiterate.
Eight years of schooling were required and over 80% of children attended.
For the few special students who went past elementary school, the high schools were based on the German gymnasium.
Competitive examinations were used to judge college applicants, and Bulgaria had a number of technical and specialized schools in addition to the University of Sofia.
Many Bulgarian students also went abroad, primarily to Germany and Austria (educational ties with Russia ended in 1917).
Overall, education reached more of the lower classes than anywhere else in Eastern Europe, but on the downside all too many students obtained degrees in the liberal arts and other abstract subjects and could not find work anywhere except in the government bureaucracy.
Many of them gravitated towards the Bulgarian Communist Party.
Since the population was 85% ethnic Bulgarians, there was relatively little social strife aside from the conflict between the haves and have-nots. Most inhabitants of Sofia maintained close ties to the countryside, but this did not prevent a rift between the peasants and urban class (i.e. Sofia versus everyone else), although some was the result of deliberate manipulation by politicians seeking to take advantage of traditional peasant distrust of the "effeminate city slicker". Mostly however, it was due to a quarrel between the rulers and the ruled. Around 14% of the population were Muslims, mostly Turks (i.e. the remnant of the landowning class), but also a handful of so-called "Pomaks" (ethnic Bulgarians who practiced Islam). The Muslim population was alienated from the dominant Orthodox Christians both due to religious and historical reasons. They neither pressed for minority rights nor tried to set up their own schools, and instead asked nothing more than to be left alone to mind their own business. The Bulgarian government obliged except for a great willingness to assist them in emigrating back to Turkey.
By comparison to economics, Bulgaria's educational system was highly successful and less than half the population were illiterate. Eight years of schooling were required and over 80% of children attended. For the few special students who went past elementary school, the high schools were based on the German gymnasium. Competitive examinations were used to judge college applicants, and Bulgaria had a number of technical and specialized schools in addition to the University of Sofia. Many Bulgarian students also went abroad, primarily to Germany and Austria (educational ties with Russia ended in 1917). Overall, education reached more of the lower classes than anywhere else in Eastern Europe, but on the downside all too many students obtained degrees in the liberal arts and other abstract subjects and could not find work anywhere except in the government bureaucracy. Many of them gravitated towards the Bulgarian Communist Party.
Kingdom of Bulgaria