It has two main rivers, the Tigris and the Euphrates; Baghdad, the capital, is at the joining of those bodies of water. One of the classic names for Iraq is "the land of the two rivers", which is part of the formal name of al-Qaeda in Iraq.
In classical times, its main region was known as Mesopotamia (Greek: "between the rivers"), and the civilizations that populated it as far back as 5,000 BCE were responsible for many early intellectual advances.
The modern boundaries of Iraq go back to the 1920s, when the British joined three former districts of the Ottoman Empire. Iraq was occupied by Britain during the course of World War I; in 1920, it was declared a League of Nations mandate under UK administration. In stages over the next dozen years, Iraq attained its independence as a kingdom in 1932.
While the classic Mesopotamia did correspond to one of the Ottoman "governorates", the British-defined state put together three provinces of distinct religious/ethnic majority, with no Iraqi identity:
- Mosul governorate: Kurdish people, ethnically Persian and largely Sunni, in the north
- Baghdad governorate: Sunni Arabs in the center, around Baghdad
- Basra governorate: Shi'a Arabs in the south
The first large-scale petroleum strikes were in Masjid-i Suleiman, in 1908, in Mosul governorate. It was approximately at the same time when oil became a critical world commodity; when the Royal Navy made every other battleship in the world obsolete with HMS Dreadnought (1905), one of its innovation was the movement from coal to oil fuel.
There has been no strong Iraqi identity. The most fundamental identity, for most Iraqis, is tribal, described as a more significant identification than the usual split into Kurdish, Sunni, and Shia. David Kilcullen observed that "Iraqi tribes are not somehow separate, out in the desert, or remote: rather, they are powerful interest groups that permeate Iraqi society. More than 85% of Iraqis claim some form of tribal affiliation; tribal identity is a parallel, informal but powerful sphere of influence in the community.
Iraqi tribal leaders represent a competing power center, and the tribes themselves are a parallel hierarchy that overlaps with formal government structures and political allegiances. Most Iraqis wear their tribal selves beside other strands of identity (religious, ethnic, regional, socio-economic) that interact in complex ways, rendering meaningless the facile division into Sunni, Shi’a and Kurd. The reality of Iraqi national character is much more complex than that, and tribal identity plays an extremely important part in it, even for urbanized Iraqis. 
Iraq's monarchy was overthrown in 1958; the Baa'th party overthrew the existing government in 1963, and Saddam Hussein rose to strict control of the Baa'th in 1979, with state control by the a complex set of police and intelligence organizations.
In the last several decades, Iraq has been involved in three major wars:
- Iran-Iraq War between 1980 and 1988, triggered by an Iraqi invasion of Iran,
- Gulf War, fought by a United Nations authorized coalition after the 1990 invasion of Kuwait by Iraq,
- Iraq War, begun by a US-led coalition in 2003.
The three wars were fought with Saddam Hussein as Head of State and government. Following the Iraq War, Hussein was tried by the new government and executed, by hanging, on 30 December 2006.
Occupation following 2003 war
Evolving new government
The CPA, after a year, transferred nominal power to a sovereign Interim Iraqi Government in June 2004. This was followed by a Transitional Government in May 2005, which drafted a constitution and held elections in late 2005, after which the current Iraqi government came into being in May 2006.