January 4 – Suicide bomber struck a Shiite funeral in Karbala, killing 32 and wounding 40.
January 5 –
50 people were killed and 80 wounded by a suicide bomb attack in the Iraqi city of Karbala.
70 people were killed and 40 injured in a suicide attack on a line of police recruits in Ramadi.
Insurgent violence shut down Iraq's largest oil refinery.
January 6 –
Thousands of Shiites demonstrated in Baghdad after two days of bloodshed that claimed almost 200 lives.
A secret Pentagon study has found that at least 80 percent of the marines who have died in Iraq due to wounds to their upper body could have survived if they had worn extra body armor. The armor has been available since 2003.
Paul Bremer, who led the U.S. civilian occupation authority in Iraq after the 2003 invasion, has admitted the United States did not anticipate the insurgency in the country, NBC television said on Friday.
Demonstrations protesting against unemployment in the Iraqi town of Nasiriyah turned violent leaving two dead and two dozen injured.
February 22 – The Al Askari Mosque bombing. Although no injuries occurred in the blast, the bombing was hugely offensive to Shi'ites and resulted in violence over the following days. The Iraqi government has stated that 379 people were killed in the subsequent attacks, although the Washington Post reported that over 1,300 people were killed.
February 28 – A bomber blew himself up near a petrol station in one of the Iraqi capital's Shia areas just before curfew and hours after other blasts killed 35.
March 12 – Abeer Qassim Hamza al-Janabi an 14 year old Iraqi girl was gang-raped and murdered together with her 6-year-old sister, mother and father, in their home, by U.S. soldiers who then set fire to the girl's body before decamping.
March 24 – Joint Center for Operational Analysis at United States Department of Defense on March 24, 2006, released a report compiled from captured Iraqi intelligence. The report stated that Russia aided Saddam's regime with correct information on the coalition invasion.
March 25 –
40 people killed or wounded in gun battle near Mahmoudiya.
US Ambassador Zalmay Khalilzad said on Saturday, March 25, that militias, many with strong ties to powerful Shiite leaders and well entrenched in security and police forces, are killing more Iraqis than terrorists.
May 10 – Iraqi President Jalal Talabani made a public announcement urging all political parties to "quell this bleeding" after figures showed sectarian violence killed 1,091 in Baghdad the prior month.
June 5 – A SEABEE convoy moving between Al Quim and Al Asad was ambushed by several IED's. Two members of NMCB-25 were killed. Petty Officer First Class Equipment Operator Gary Rovinski and Petty Officer Second Class Hospital Corpsman Jamie Jaenke.
June 7 – Al-Qaeda in Iraq leader Abu Musab al-Zarqawi is killed by an American air strike. Zarqawi was a Jordanian militant who had called for attacks against Shi'ites. Most Iraqis hoped his death will help ease sectarian bloodshed, much of which was masterminded by him.
July 1 – Attacks in the Shi'ite slum of Sadr City in Baghdad killed 66 people.
July 9 – Shia gunmen allegedly massacred 40 Sunni Muslims in Baghdad after setting up fake security checkpoints a day after the Shi'ite Zahra mosque in the area was bombed.
July 18 – A car bomb killed 53 people in the holy Shi'ite city of Kufa.
In July 2006, Baghdad's central morgue received 1,855 bodies, the most since the bombing of a Shia shrine in February prompted a wave of sectarian killings. The Iraqi government stated that 3,438 Iraqis died around the country that month.
September 27 – A WPO poll found that seven out of ten Iraqis want U.S.-led forces to withdraw from Iraq within one year. The perception that the U.S. presence in Iraq has a negative impact on security is widespread and is given some support by the British withdrawal from Basra which led to a 90% reduction in violence. Overall, 78% of those polled said they believed that the presence of U.S. forces is "provoking more conflict than it's preventing." 53% of those polled believed the Iraqi government would be strengthened if U.S. forces left Iraq (versus 23% who believed it would be weakened), and 71% wanted this to happen in 1 year or less. All of these positions are more prevalent amongst Sunni and Shia respondents than among Kurds. 61% of respondents said that they "approve" of attacks on U.S.-led forces, while 94% still had an unfavorable opinion of al-Qaeda.
In September 2006, The Washington Post reported that the commander of the Marine forces in Iraq filed "an unusual secret report" concluding that the prospects for securing the Anbar province are dim, and that there is almost nothing the U.S. military can do to improve the political and social situation there.
November 23 – The deadliest attack since the beginning of the Iraq war occurred. Suspected Sunni-Arab militants used five suicide car bombs and two mortar rounds on the capital's Shiite Sadr City slum to kill at least 215 people and wound 257. Shiite mortar teams quickly retaliated, firing 10 shells at Sunni Islam's most important shrine in Baghdad, badly damaging the Abu Hanifa mosque and killing one person. Eight more rounds slammed down near the offices of the Association of Muslim Scholars, the top Sunni Muslim organisation in Iraq, setting nearby houses on fire. Two other mortar barrages on Sunni neighborhoods in west Baghdad killed nine and wounded 21, police said.
November 28 – Another Marine Corps intelligence report was released confirming the previous report on Anbar stating that, "U.S. and Iraqi troops 'are no longer capable of militarily defeating the insurgency in al-Anbar,' and 'nearly all government institutions from the village to provincial levels have disintegrated or have been thoroughly corrupted and infiltrated by Al Qaeda in Iraq.'"