Iraqi civil war (2006–2008) in the context of "Iraqi insurgency (2003–2011)"

Samarra (Arabic: سَامَرَّاء, Sāmarrāʾ) is a city in Iraq. It stands on the east bank of the Tigris in the Saladin Governorate, 125 kilometers (78 mi) north of Baghdad. The modern city of Samarra was founded in 836 by the Abbasid caliph al-Mu'tasim as a new administrative capital and military base. In 2003 the city had an estimated population of 348,700. During the Iraqi Civil War (2006–08), Samarra was in the "Sunni Triangle" of resistance.

The archeological site of Samarra still retains much of the historic city's original plan, architecture and artistic relics. In 2007, UNESCO designated it a World Heritage Site.

The Al-Askari Shrine (Arabic: مَرْقَد ٱلْإِمَامَيْن عَلِيّ ٱلْهَادِي وَٱلْحَسَن ٱلْعَسْكَرِيّ, romanized: Marqad al-ʾImāmayn ʿAlī al-Hādī wal-Ḥasan al-ʿAskarī, lit. 'Resting Place of the Two Imams Ali al-Hadi and Hasan al-Askari'), also known as the 'Askariyya Shrine and the Al-Askari Mosque, is a Twelver Shi'ite mosque and mausoleum, located in the city of Samarra, in the Saladin Governorate of Iraq.

Built in 944 CE, it is one of the most important Shia shrines in the world. The dome was destroyed in a bombing by Sunni extremists in February 2006 and its two remaining minarets were destroyed in another bombing in June 2007, causing widespread anger among Shias and instigation of the Iraqi Civil War between the country's Shia and Sunni factions. The remaining clock tower was also destroyed in July 2007. The dome and minarets were repaired and the mosque reopened in April 2009.

After the 2003 invasion of Iraq was completed and the regime of Saddam Hussein was toppled in May 2003, an Iraqi insurgency began that would last until the United States left in 2011. The 2003–2006 phase of the Iraqi insurgency lasted until early 2006, when it escalated from an insurgency to a Sunni-Shia civil war, which became the most violent phase of the Iraq War.

Sectarian violence in Iraq refers to the conflict that had developed in the aftermath of the 2003 invasion of Iraq as a result of rising sectarian tensions between the different religious and ethnic groups of Iraq, most notably the conflict between extremist Shi'ite groups and extremist Sunni groups, which escalated into a full-scale civil war between 2006 until 2008, and had largely ceased following the defeat of ISIS in 2017 during the 2013–2017 war in Iraq.

According to most sources, including the CIA's World Factbook, the majority of Iraqis are Shi'i Arab Muslims amounting to around 64% to 69% of the population, whereas Sunni Muslims represent between 32% and 37% of the population. Furthermore, the Sunnis are split ethnically among Arabs, Kurds and Turkmen.

On May 1, 2003, United States president George W. Bush gave a televised speech on the aircraft carrier USS Abraham Lincoln near the coast of California. Bush, who had launched the U.S.-led invasion of Iraq six weeks earlier, mounted a podium in front of a White House-produced banner that read "Mission Accomplished". Reading from a prepared text, he said, "Major combat operations in Iraq have ended. In the battle of Iraq, the United States and our allies have prevailed ... because the regime [of Iraqi dictator Saddam Hussein] is no more." Although Bush went on to say that "Our mission continues" and "We have difficult work to do in Iraq", his words implied that the Iraq War was over and the United States-led Coalition forces had won.

Bush's assertions—and the sign itself—became controversial as the Iraqi insurgency gained pace and developed into an outright sectarian war, with the vast majority of casualties—Coalition forces and Iraqi, military and civilian—occurring after the speech. U.S. troops fought in Iraq for eight more years, before eventually withdrawing in 2011. In modern cultural parlance, the phrase "Mission Accomplished" is frequently used to refer to the perils of declaring victory too early in crises.