The Balkans in the early 20th century was predisposed to conflicts. The piecemeal expulsion of ailing imperial power, the Ottomans, created new states – Bulgaria, Serbia, Montenegro, Albania – and incorporated both Greece and Romania into the geographical make-up of the region. But fired by liberation, the arbitrary boundaries brokered by the Great Powers satisfied no-one. Serbia considered Bosnia and Herzegovina naturally part of a Greater Serbia, and was enraged by its annexation by Austria-Hungary in 1908. Bulgaria’s pursuit of a Greater Bulgaria provoked three wars with Macedonia, a zone of contention between its neighbouring states. Austria-Hungary was determined to prevent Slavic nationalism infecting its own dominions, while Russia encouraged it to extend its sphere of influence. German and Magyar minorities in Romania tended to align with Austria-Hungary, while groups like the Vlachs (Catholic pastoralists) and Pomaks (Slav Muslims) were widely distributed and frequently distinctive in their sympathies.
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