How did Bulgaria become part of the Soviet sphere of influence after World War II?

Bulgaria’s transition into the Soviet sphere of influence was facilitated by both geopolitical agreements and internal political maneuvering. In October 1944, British Prime Minister Winston Churchill signaled his willingness to consign Bulgaria to Soviet control during his "percentages discussion" with Joseph Stalin.12

On the ground, the Fatherland Front—a coalition led by the Bulgarian Communist Party—seized power through a coup d’état on September 9, 1944, just as Soviet troops entered the country. Following the war, the new regime systematically eliminated political opposition through "people’s courts," which executed thousands of officials and political rivals.3412

The communists further consolidated control by:
* Rigging elections and forcing the exile of Tsar Simeon II, leading to the proclamation of a republic in 1946.12
* Executing key opposition leaders, such as Nikola Petkov.12
* Forcing the "self-liquidation" of noncommunist parties and absorbing others into the Fatherland Front.12
* Enacting the "Dimitrov Constitution" in 1947, which was modeled on the 1936 Soviet constitution.12