Iraq

The Tigris and Euphrates flow from Turkey through Iraq toward the Persian Gulf. Much of central and southern Iraq is dry, so for thousands of years people have channeled river water into fields to grow crops and support towns and cities. These river valleys helped support some of the world's earliest civilizations, and farms and communities still depend heavily on both rivers today.

Central and southern Iraq contain a broad, fertile plain that helped support some of the world's earliest cities. Over thousands of years, the Tigris and Euphrates built up this flat land by depositing mud and soil carried downstream. This region is part of ancient Mesopotamia, whose name means "land between the rivers." People have irrigated and farmed the plain for thousands of years, growing crops such as wheat, barley, and date palms, and it remains one of Iraq's main areas for farming and settlement.

Iraq's landscape changes dramatically from dry desert in the west to cooler, wetter mountains in the north and northeast. More than a third of the country lies in the western desert and dry steppe, where far fewer people live than along the rivers. In the north and northeast, the land rises into rugged highlands near Turkey and Iran, with peaks above 3,000 meters. These mountains receive more rain, support more farming, and are home to much of Iraq's Kurdish population.

Southern Iraq contains a vast wetland of shallow lakes and reed beds known as the Mesopotamian Marshes. The marshes form where water from the Tigris and Euphrates spreads across the flat land near the Persian Gulf. Marsh Arab communities have adapted to this watery environment for generations, traditionally traveling by boat, building with reeds, fishing, and raising water buffalo. Much of the marshland was deliberately drained in the 1990s, but large areas were later reflooded and restored; today the marshes are part of a UNESCO World Heritage Site. Farther south, Iraq reaches the Persian Gulf through a very short coastline near Basra, giving the country its main connection to ocean trade.

Water strongly shapes where people live in Iraq: most Iraqis live near the Tigris and Euphrates or in the wetter north, while the western desert has far fewer people. Iraq's largest cities follow this pattern: Baghdad grew on the Tigris in the center of the country, Basra developed near the Persian Gulf and became its main port, and Mosul and Erbil anchor the more populated north.

Iraq is home mainly to Arabs and Kurds, with most Kurdish communities concentrated in the mountainous north and northeast. Kurdish populations also extend across the borders into Turkey, Iran, and Syria, and Kurdish communities have their own languages and cultural traditions. In northern Iraq, the Kurdistan Region has its own regional government within Iraq. Iraq is also home to smaller Turkmen, Assyrian, and other communities with their own languages and traditions.

Most Iraqis are Muslim. Iraq's Muslim population includes two major branches of Islam: Shia and Sunni. Shia Muslims are especially numerous in central and southern Iraq, while many Sunni communities live in western and northern areas. Iraq is also home to Christian, Yazidi, Mandaean, and other religious communities with long histories in the region.

Some of the world's earliest writing developed in ancient Mesopotamia, in the land that is now Iraq. Centuries later, Baghdad became one of the world's great centers of scholarship during the Abbasid Caliphate, an empire that ruled much of the Middle East and surrounding regions beginning in the 700s. By around 800 CE, Baghdad may have had about a million residents and was among the largest cities on Earth.

Iraq has some of the world's largest underground petroleum reserves, making oil the country's most important natural resource. Many of its biggest oil fields lie in southern Iraq near Basra. Pipelines carry oil toward the Gulf, where it is loaded onto tanker ships and exported around the world. Oil dominates Iraq's exports and provides most of the money the national government receives, so the geography of this southern region has an enormous effect on the country's economy.

Farmers have depended on the Tigris and Euphrates for thousands of years, but today that water is becoming less reliable. Farmers grow wheat, barley, vegetables, fruit, and dates, while drought, hotter temperatures, and declining river flows make farming more difficult. In some irrigated areas, salt can also build up in the soil as water evaporates, making crops harder to grow.

Iraq does not control the sources of its two most important rivers. The Tigris and Euphrates begin mainly in Turkey and flow downstream toward Iraq, with parts of the river system also passing through Syria. Dams, irrigation, drought, and water use upstream can change how much water eventually reaches Iraqi farms, cities, and marshes. This makes water an important connection—and sometimes a source of disagreement—between Iraq and its neighbors.

Northern Iraq includes the Kurdistan Region, which is part of Iraq but has its own parliament and regional government. It controls many of its own internal affairs while remaining part of the Iraqi state. This gives the predominantly Kurdish region more self-government than other parts of the country.