They were left stateless when Britain and France, the colonial powers which won WW1, carved up on the Ottoman Empire.
The Kurds claim Iraq has failed to respect autonomy established after Saddan Hussein was overthrown in 2003, Kurds feel they were not given a fair deal even after their crucial contribution in confronting Islamic State.
All registered residents - both Kurds and non-Kurds - of the KRG, internally displaced Kurds, and Kurdish diaspora will be taking part in the voting.
If the referendum result is in favor of KRG, they want to press for negotiations with Baghdad and neighboring countries to achieve independence.