Bulgaria was self ruled with Monarchy and Parliament. When The Nazis came into power and Bulgaria became part of the Axis powers they were not completely dedicated to the Nazi causes or invasions of other countries. The story is long and complex so I am giving you a link below where you can read about Bulgaria in World War 2.
bg
Named of a tribe
union makes the power
If you mean what is bulgarians religion. They are Christians.
around 7 million
box by Kubrat Pulev
Around 7 300 000 people
mommy
Until 1989, Bulgaria was a communist state.
Romas
Sofia is Bulgaria's largest city, with a population of 1,152,556.
From the ancestors of Han Asparukh (the founder of Bulgarian state)