Nzhdeh played a key role in organizing the troops for the defense of Karakilisa in May 1918. He managed to mobilize a population of despairing and hopeless locals and refugees for the coming fight through his inspiring speech in the Dilijan church courtyard, where he called on the Armenians to wage a sacred battle: "Straight to the frontline, our salvation is there." Nzhdeh was wounded in the ensuing clash and, after a violent battle of four days, both sides had serious casualties. The Armenians ran out of ammunition and had to withdraw. Although the Ottoman army managed to invade Karakilisa itself, they had no more resources to continue deeper into Armenian territory. After the declaration of the independent First Republic of Armenia, Nzhdeh was appointed governor of Nakhijevan, and later on, in August 1919, commander of the southern corps of the Armenian army.