evidence: A considerable degree of hostility existed between Armenia and its new neighbor to the east, the Democratic Republic of Azerbaijan, stemming largely from racial, religious, cultural and societal differences. The Azeris had close ethnic and religious ties to the Turks and had provided material support for them in their drive to Baku in 1918. Although the borders of the two countries were still undefined, Azerbaijan claimed most of the territory Armenia was sitting on, demanding all or most parts of the former Russian provinces of Elizavetpol, Tiflis, Yerevan, Kars and Batum.[115] As diplomacy failed to accomplish compromise, even with the mediation of the commanders of a British expeditionary force that had installed itself in the Caucasus, territorial clashes between Armenia and Azerbaijan took place throughout 1919 and 1920, most notably in the regions of Nakhichevan, Karabakh, and Syunik (Zangezur). Repeated attempts to bring these provinces under Azerbaijani jurisdiction were met with fierce resistance by their Armenian inhabitants. In May 1919, Dro led an expeditionary unit that was successful in establishing Armenian administrative control in Nakhichevan.[116]