This presentation focuses on the role of the environmental factors in bringing about the Sheikh Ubeiduallah Rebellion. This rebellion started in the last months of 1880, when tens of thousands of Iranian and Ottoman Kurds marched on northwestern Iran. Under the command of Sheikh Ubeidullah of Nehri, an Ottoman citizen and influential leader of a Sunni religious brotherhood, they temporarily took control of several cities. Their success, followed by the aggressive response of the Iranian army, activated what had been relatively dormant Shia-Sunni sectarian boundaries and resulted in great violence and displacement: tens of thousands of families left their ancestral lands, villages and towns were depopulated, civilians lost their lives, and the affected districts were laid to waste. The memories of the revolt shaped the relations between the Iranian Kurds and the Iranian state for a long time to come. In the literature on the Kurds this revolt has been characterized as the cradle of Kurdish nationalism. No doubt nationalist aspirations, and some other factors contributed to the making of this rebellion. This paper argues and shows that environmental factors, including famines of 1860-1 and 1873, significantly contributed to the making of this revolt.