Iraq, which occupies an area once home to some of the earliest known civilisations, has been a battleground for competing forces since the US-led ouster of President Saddam Hussein in 2003.
The mainly Shia-led governments that have held power since have struggled to maintain order, and the country has enjoyed only brief periods of respite from high levels of sectarian violence.
Instability and sabotage have hindered efforts to rebuild an economy shattered by decades of conflict and sanctions, even though Iraq has the world's second-largest reserves of crude oil.
Republic of Iraq
Population 37 million
Area 438,317 sq km (169,235 sq miles)
Major languages Arabic, Kurdish
Major religion Islam
Life expectancy 68 years (men), 73 years (women)
Currency Iraqi dinar
President: Barham Salih
Veteran Iraqi Kurdish politician Barham Salih was elected by parliament in October 2018 to serve the first of a maximum of two four-year terms in the largely ceremonial post.
Under an informal agreement between political parties, the presidency is reserved for Kurds, the premiership for Shia Arabs, and the post of speaker of parliament for Sunni Arabs.
There are hundreds of publications and scores of radio and TV stations. But political and security crises have resulted in an increasingly fractured media scene.
Television is the main medium for news. Many media outlets have political or religious affiliations.
Some key dates in Iraq's history:
1534-1918 - Ottoman rule.
1917 - Britain seizes control, creates state of Iraq.
1932 - Independence, followed by frequent coups.
1979 - Saddam Hussein becomes president.
1980-1988 - Iran-Iraq war.
1990 - Iraq invades Kuwait, putting it on a collision course with the international community.
2003 - US-led coalition invades, starting years of guerrilla warfare and instability.
2014 - The armed Islamic State group emerges as a major force in the region and seizes large parts of Iraq, which it holds until a government offensive drives it out in 2017.