This episode covers the first half of Season 7, roughly 1879 until 1886. In that time, Bulgaria drafted its first constitution, found itself a Prince, and generally attempted to lay the groundwork for the reclamation of the territories it had been promised in the Treaty of San Stefano. However, hampering all of these efforts was intense Russian meddling including wildly inconsistent policies. Ultimately, when unification with Eastern Rumelia came unexpectedly, Russia broke off diplomatic relations and Serbia invaded. Despite a victory, Battenberg ultimately had to abdicate.
Bulgaria after the Congress of Berlin