Iraq, often called the “cradle of civilization,” has a history that stretches back to the dawn of human civilization itself. Situated in Mesopotamia, between the Tigris and Euphrates rivers, Iraq is where some of the world’s earliest civilizations emerged, including the Sumerians, Akkadians, Babylonians, and Assyrians. Throughout its long and complex history, Iraq has been shaped by numerous empires, invasions, and political regimes, including Persian, Greek, and Islamic caliphates. In modern times, Iraq has experienced political upheavals, wars, and dictatorial rule, notably under Saddam Hussein, followed by the U.S.-led invasion in 2003 and the ongoing challenges of rebuilding after decades of conflict. This timeline explores Iraq’s major historical periods from ancient Mesopotamia to the modern-day republic.

Ancient Mesopotamia (circa 6000 BCE – 539 BCE)

The Rise of Sumer (circa 4500 BCE – 2270 BCE)

• The earliest known civilization in Iraq was Sumer, which developed around 4500 BCE in southern Mesopotamia. Sumerians are credited with inventing the cuneiform script, one of the first writing systems.
• The Sumerians built the first city-states, such as Ur, Uruk, and Lagash, and developed advanced technologies, including irrigation, the wheel, and early forms of mathematics and astronomy.
• Gilgamesh, the legendary king of Uruk, is celebrated in the Epic of Gilgamesh, one of the oldest known works of literature.

The Akkadian Empire (circa 2334 BCE – 2154 BCE)

• In 2334 BCE, Sargon of Akkad established the Akkadian Empire, the world’s first known empire, uniting the city-states of Mesopotamia under a centralized rule.
• The Akkadians absorbed Sumerian culture but spread their Semitic language, which became the dominant language in the region.
• The Akkadian Empire fell around 2154 BCE due to internal strife and external invasions by the Gutians, a nomadic people from the Zagros Mountains.

The Babylonian Empire and the Code of Hammurabi (circa 1894 BCE – 539 BCE)

• The city of Babylon rose to prominence under King Hammurabi (r. 1792–1750 BCE), who is best known for creating the Code of Hammurabi, one of the earliest written legal codes.
• Babylon became a cultural and religious center, dedicated to the god Marduk. The Hanging Gardens of Babylon, one of the Seven Wonders of the Ancient World, was reportedly built during this period.
• The Kassites conquered Babylon around 1595 BCE, but Babylon regained its power in the Neo-Babylonian period (626–539 BCE) under Nebuchadnezzar II, who rebuilt the city and expanded the empire.

The Assyrian Empire (circa 2500 BCE – 609 BCE)

• In northern Mesopotamia, the Assyrian Empire emerged, known for its military prowess and administrative efficiency. At its height, it controlled an empire stretching from Egypt to Persia.
• Ashurbanipal (r. 668–627 BCE), one of the greatest Assyrian kings, is remembered for creating the Library of Nineveh, which preserved thousands of cuneiform tablets.
• The Assyrian Empire fell in 609 BCE after a coalition of Babylonians and Medes sacked Nineveh, marking the end of Assyrian dominance.

Persian, Greek, and Roman Periods (539 BCE – 637 CE)

The Achaemenid Persian Empire (539 BCE – 331 BCE)

• In 539 BCE, Cyrus the Great of the Achaemenid Empire conquered Babylon, integrating Mesopotamia into his vast empire, which stretched from Greece to India.
• Under Persian rule, Mesopotamia became a key province, with Persian kings such as Darius I and Xerxes I overseeing the construction of canals and roads that improved trade and communication.
• The Zoroastrian religion became prominent during this period, though the region retained much of its Mesopotamian culture and identity.

The Hellenistic Period: Alexander the Great and the Seleucids (331 BCE – 141 BCE)

• In 331 BCE, Alexander the Great defeated the Persians at the Battle of Gaugamela, bringing Mesopotamia under Greek rule. After Alexander’s death in 323 BCE, his empire was divided among his generals.
• Mesopotamia became part of the Seleucid Empire, founded by Seleucus I Nicator, one of Alexander’s generals. Greek culture, language, and philosophy spread throughout the region, although traditional Mesopotamian religions and customs persisted.

Parthian and Sassanian Empires (141 BCE – 637 CE)

• In 141 BCE, the Parthians took control of Mesopotamia, establishing the Parthian Empire, which lasted for nearly five centuries. The Parthians maintained a decentralized state and often clashed with the Roman Empire.
• The Sassanian Empire replaced the Parthians in 224 CE and reasserted Persian control over Mesopotamia. The Sassanians promoted Zoroastrianism as the state religion and fostered a revival of Persian culture and art.
• Under the Sassanians, Mesopotamia remained a wealthy and strategically important region, although it experienced frequent wars with the Romans and Byzantines.

The Islamic Conquest and the Abbasid Caliphate (637 CE – 1258 CE)

The Islamic Conquest (637 CE – 750 CE)

• In 637 CE, the Rashidun Caliphate under Caliph Umar defeated the Sassanian forces at the Battle of al-Qadisiyyah, marking the beginning of Islamic rule in Mesopotamia.
• The city of Kufa was established as an important garrison town, and Islam spread throughout the region, gradually replacing Zoroastrianism and older Mesopotamian religions.
• By the end of the Umayyad Caliphate (661–750 CE), Mesopotamia had become a central part of the Muslim world, with Baghdad emerging as a significant cultural and political center.

The Abbasid Caliphate and the Golden Age of Islam (750 CE – 1258 CE)

• In 750 CE, the Abbasid Caliphate overthrew the Umayyads and moved the capital to Baghdad, which became the center of the Islamic world. The Abbasid era is often referred to as the Golden Age of Islam, marked by advancements in science, medicine, philosophy, and literature.
• Harun al-Rashid (r. 786–809 CE) and his son Al-Ma’mun (r. 813–833 CE) are remembered for their patronage of scholars and the establishment of the House of Wisdom, a major intellectual center that attracted scholars from across the Islamic world.
• During the Abbasid period, Baghdad became one of the largest and most cosmopolitan cities in the world, with flourishing trade, science, and culture.
• The Abbasid Caliphate began to decline in the 10th century, with power increasingly falling into the hands of regional rulers, while the caliphate remained a symbolic religious authority.

The Mongol Invasion and the Fall of Baghdad (1258 CE)

• In 1258 CE, the Mongols under Hulagu Khan sacked Baghdad, bringing an end to the Abbasid Caliphate’s political power. The destruction of Baghdad marked the collapse of the city as a major center of culture and learning.
• The Mongol invasion caused widespread devastation in Mesopotamia, and the region was subsequently ruled by a series of Mongol and Turkic dynasties, including the Ilkhanate and later the Timurids.

Ottoman Empire and British Mandate (1534 CE – 1932 CE)

The Ottoman Empire (1534 CE – 1918 CE)

• In 1534 CE, the Ottoman Empire under Sultan Suleiman the Magnificent captured Baghdad, incorporating Mesopotamia into the Ottoman realm.
• For nearly four centuries, Iraq was ruled as a province of the Ottoman Empire, with a relatively decentralized administration. The Ottomans were primarily interested in Iraq as a buffer zone between their empire and the Safavid Empire of Persia.
• Ottoman control over Iraq was often tenuous, with frequent tribal revolts and regional autonomy, particularly in the southern provinces of Basra and Najaf.
• By the 19th century, Iraq became more integrated into the Ottoman Empire, but it remained underdeveloped and plagued by sectarian divisions, particularly between the Sunni and Shia Muslim populations.

British Occupation and the Mandate (1918 CE – 1932 CE)

• During World War I, British forces invaded Iraq and captured Baghdad in 1917. Following the collapse of the Ottoman Empire in 1918, Iraq came under British control as part of the Mandate for Mesopotamia established by the League of Nations.
• In 1920, a major revolt against British rule, known as the Iraqi Revolt, erupted, driven by opposition to foreign control and dissatisfaction among Iraq’s tribal and religious groups.
• In 1921, the British installed King Faisal I, a member of the Hashemite family, as the king of Iraq. Faisal’s monarchy was established with British support, but the country remained a British protectorate until 1932, when Iraq gained nominal independence as the Kingdom of Iraq.

Independence and the Kingdom of Iraq (1932 CE – 1958 CE)

The Kingdom of Iraq (1932 CE – 1958 CE)

• Iraq gained formal independence in 1932, becoming a sovereign state under King Faisal I. However, Britain retained significant influence over Iraq’s military, economy, and foreign policy.
• Iraq was marked by political instability, with frequent military coups and growing opposition to the monarchy, particularly from nationalist and communist groups.
• King Faisal II, who succeeded his father, faced increasing unrest as Iraqis demanded greater control over the country’s resources, particularly its oil industry, which was dominated by British companies.

The 1958 Revolution and the Fall of the Monarchy

• In 1958, a group of Iraqi military officers, led by Brigadier General Abdul Karim Qasim, overthrew the monarchy in a coup known as the 14 July Revolution. King Faisal II was executed, and Iraq was declared a republic.
• Qasim’s government pursued a policy of non-alignment during the Cold War, balancing relations with both the Soviet Union and the West, while also promoting land reforms and efforts to nationalize Iraq’s oil industry.
• Qasim’s regime was marked by internal divisions, and in 1963, he was overthrown in a coup led by Ba’athist and nationalist officers.

Ba’athist Rule and Saddam Hussein (1968 CE – 2003 CE)

Rise of the Ba’ath Party (1968 CE – 1979 CE)

• In 1968, the Ba’ath Party, a pan-Arab nationalist movement, seized power in Iraq. Ahmed Hassan al-Bakr became president, while Saddam Hussein, a rising figure within the party, gained increasing control over Iraq’s security apparatus.
• During this period, Iraq’s oil revenues soared following the 1973 oil crisis, enabling the government to invest in large-scale infrastructure projects and social programs. However, political repression and human rights abuses became more widespread.

Saddam Hussein’s Rule (1979 CE – 2003 CE)

• In 1979, Saddam Hussein officially became president of Iraq, consolidating his power through purges and a vast network of security forces.
• Saddam’s regime was characterized by authoritarianism, the use of secret police, and widespread surveillance. He launched aggressive modernization programs, but also brutally suppressed dissent, particularly from Shia Muslims and Kurds.
• In 1980, Iraq launched a war against Iran that would last for eight years, costing hundreds of thousands of lives and devastating Iraq’s economy.
• In 1990, Saddam invaded Kuwait, leading to the Gulf War in 1991, during which a U.S.-led coalition expelled Iraqi forces from Kuwait. The war resulted in severe economic sanctions on Iraq and widespread internal unrest, including uprisings by Shia and Kurdish populations that were violently suppressed by Saddam’s forces.
• Throughout the 1990s, Iraq faced crippling sanctions, economic collapse, and growing isolation, but Saddam Hussein maintained his grip on power.

U.S. Invasion and Modern Iraq (2003 CE – Present)

The U.S.-Led Invasion of Iraq (2003 CE)

• In 2003, the United States, under President George W. Bush, invaded Iraq, accusing Saddam Hussein of possessing weapons of mass destruction (WMDs) and supporting terrorism. The invasion quickly toppled Saddam’s regime, but no WMDs were found.
• Saddam Hussein was captured by U.S. forces in 2003 and executed in 2006 after being tried by an Iraqi court for crimes against humanity.

Post-Invasion Iraq and Sectarian Conflict (2003 CE – 2011 CE)

• After Saddam’s fall, Iraq descended into sectarian violence between Sunni, Shia, and Kurdish groups. The U.S.-backed government struggled to establish stability, while insurgent groups, including al-Qaeda in Iraq, gained strength.
• In 2006, Iraq’s sectarian tensions exploded into full-scale civil war, particularly between Sunni and Shia militias. The violence led to tens of thousands of deaths and the displacement of millions of Iraqis.
• In 2011, the U.S. formally withdrew its forces from Iraq, leaving behind a fragile and divided country still facing internal conflict and instability.

The Rise of ISIS and the Struggle for Stability (2011 CE – Present)

• In 2014, the extremist group ISIS (Islamic State of Iraq and Syria) captured large swathes of Iraqi territory, including the major city of Mosul, declaring a caliphate and committing widespread atrocities.
• A U.S.-led coalition, along with Iraqi government forces and Kurdish Peshmerga, launched a campaign to defeat ISIS. By 2017, ISIS had lost most of its territory in Iraq, though the group continues to operate as an insurgency.
• Iraq has since focused on rebuilding and recovering from the devastation caused by ISIS, though the country continues to face challenges, including corruption, sectarian divisions, and economic instability.