Unfranked cover to Athens,Greece from a Greek officer (second lieutenant) of the 'Greek Military Mission in Sofia, Bulgaria'. Postmarked for dispatch with ‘ΣΤΡ. ΤΑΧΥΔΡΟΜΕΙΑ 900* 9 ΑΠΡ 19 [(Greek) Army Postal Sector 900, 9 APR 19’]. Handstamped with 3-circled cachet texted 'EΛΛΗΝΙΚΗ ΣΤΡΑΤΙΩΤΙΚΗ ΑΠΟΣΤΟΛΗ * ΕΝ ΒΟΥΛΓΑΡΙΑ' , [Greek Military Mission in Bulgaria] in outer belt with a central crest. On arrival postmarked ‘AΘΗΝΑΙ (ΑΦΙΞΙΣ) * 18 ΑΠΡ 19’ (faint).

Addressee, Miss Nefeli Despotopoulou, is known along with her two sisters Georgia and Ioanna for having kept correspondence with Greek enlisted men in all fronts from 1912 (Balkan Wars) to 1922 (end of the expedition to Turkey). The large number “36” with pencil on cover indicates sender’s incoming letter, individually numbered upon receipt in his personal
file, for reference as each man’s letter was always answered.

NΟΤΕ: On September 29, 1918, while the Great War was raging, the Bulgarians requested an unconditional armistice from the Supreme Commander of the Allied Forces on the Macedonian Front, Franchet D’Esperéy, and, abandoning their Austro-German allies, signed an armistice in Thessaloniki. Greece was also tasked with supervising this armistice and the implementation of the Treaty of Neuilly (November 27, 1919), participating in an inter-allied mission led by Colonel K. Mazarakis-Ainian, who, from this position, played a key role in the final decision to assign Western Thrace to Greece. Later a Greek military postal service was established in Sofia (Postal Sector 921) by order of the Allied General Staff based in Constantinopole, to serve the interests of the Allies.