ocr: Bulgaria was part oft the Ottoman empire for: five centuries until its independence in 1908.1 Under Ring Ferdinand, it took. sides with Germany during World War I, and. subsequently lost valuable terrtoryto Greece and Serbia. Under Ring Boris, Bulgaria once again sided with Germany in World War II. 01943 Ring Boris dies. a 1944. Allies fire-bomb Sofia. Soviet Army invades. Anti: fascist Fatherland Front coalition (FF), including Agrarian Party and Bulgarian Communist Party (BCP), takes power in bloodless coup. Rimon Georgiev prime minister. a 1946 September:: referendum abolishes monarchy. Rep ...