Nikol Duman (Nikoghayos Ter-Hovhannisyan) was born on 12 January, 1867 in the family of a priest in the village Gshlagh of Shoushi district.
In 1887 he graduated from the Shoushi diocesan school. Then he taught in Armenian schools in the North Caucasus until 1891, when he moved to Tabriz, where he was a teacher and at the same time the treasurer of the circle of local Armenian national figures. Since 1893 he taught at the school in the village Galasar of Salmas region (Iran, near the border with Turkey), where he took an active part in the Armenian national and political life as a member of the Union of Armenian revolutionaries. He was one of the three members of the committee ARF in Tabriz, along with Hovnan Davtiyan and Hovsep Arghutyan. After the Armenian massacres in 1894-1896, Nikol entirely devoted himself to the Armenian national liberation movement and organisation of self-defense.
In 1895, he moved to Van with a group of 10 people. There Nikol with 11 satellites was besieged in the house with Kurdish horsemen from Hamidiye Cavalry who were in the service of the Sultan. Although the Kurds set fire to the house, Nikol managed to escape under the cover of smoke: firing back he went to the mountains, where he killed two Kurdish beks. Admiring his courage, the Kurds nicknamed him “Duman” (“Smoke”) and wrote songs about him.
He was arrested in Van, but soon released.
In 1897, Nikol was the initiator of the 1897 Khanasor campaign (major expedition against the Kurdish commander in the Turkish service of Sharif bek and his tribe). He took part in that campaign as the squad commander.
After that, he moved back to Russia (Tiflis). During the 1904 Sasun uprising, he tried to get with his men to Sasun, but this attempt failed.
At the beginning of the Armenian-Tatar massacre in February 1905, he was hastily called by telegraph to Baku, where he organised a self-defense and, on 7 February, had successfully entered into the battle with pogrom-mongers. Duman was then appointed the head of the self-defense of Erivan province. On the question of liberation of Western Armenia he was a supporter of a general uprising. He took part in the congresses of Dashnaktsutyun party (The Armenian Revolutionary Federation (ARF)) and in 1910, was present at the Second Copenhagen International Congress.
In 1914, he became ill with tuberculosis and went for treatment in Kislovodsk. At the same time, the First World War was beginning. Feeling that he would not be able to participate in the Volunteer Movement, Duman committed suicide with a pistol shot in the evening of 23 September 1914. He was buried in Tbilisi, at the Armenian Pantheon of Tibilisi, next to the grave of one of the founders of the Armenian Revolutionary Federation, Simon Zavaryan. The pantheon with the tombs of prominent Armenians was destroyed by the government of the Georgian SSR (Soviet Socialist Republic) in the 1930s.