The DAR 10 was designed by Zvetan Lazarov in 1938 in the DAR (Darzhavna Aeroplanna Rabotilnica, meaning literally 'State Airplane Workshop') factory in Bozhurishte, near the capital Sofia.
An inauguration ceremony for the airline and its first scheduled air service, between Sofia, Ruse, and Varna, was held at Sofia Bozhurishte Airport on 25 October 1927.
The East Bulgarian began to be developed at the end of the 19th century at the "Kabiuk" stud farm (former Vassil Kolarov) near Shumen and at stud farm in Bozhurishte near Sofia, in Bulgaria, by crossing local horses with Arabians, Anglo-Arabians, Thoroughbreds and English half-breds.