The establishment of the Kurdistan Region of Iraq dates back to the March 1970 autonomy agreement between the Kurdish opposition and the Iraqi government after years of heavy fighting. The Iran-Iraq war during the 1980s and the Anfal genocide campaign of the Iraqi army devastated the population and nature of Iraqi Kurdistan. Following the 1991 uprising of the Iraqi people against Saddam Hussein, many Kurds were forced to flee the country to become refugees in bordering regions of Iran and Turkey. A northern no-fly zone was established following the First Gulf War in 1991 to facilitate the return of Kurdish refugees. As Kurds continued to fight government troops, Iraqi forces finally left Kurdistan in October 1991, leaving the region to function de facto independently; however, neither of the two major Kurdish parties had at any time declared independence and Iraqi Kurdistan continues to view itself as an integral part of a united Iraq but one in which it administers its own affairs. The 2003 invasion of Iraq and the subsequent political changes led to the ratification of a new Constitution of Iraq in 2005. The new Iraqi constitution defines Iraqi Kurdistan as a federal entity of Iraq, and establishes Arabic and Kurdish as Iraq's joint official languages. Read More .