Together, these three vilayets were home to a wide variety of different ethnic and religious groups which all lived in relative tolerance under Ottoman rule, although the Shi'i community was largely excluded from administrative positions and the army.
Zoe Preston states that this decision to back Sunni Arab political leadership, despite being a minority in Iraq, created an exclusion of other religious and ethnic groups.
Although Faisal I repeatedly tried to bring cultural values and practices of Shi'ites, Sunnis and other populations together within the context of Pan-Arabism, the outcome was a more visible distinction between the ethnic and religious groups of Iraq.
[5] These different tensions eventually resulted in the 14 July Revolution of 1958 in which the Hashemite monarchy was overthrown by a group of army officers under the leadership of General Abd al-Karim Qasim who then founded the Republic of Iraq.
[9] These tensions, along with disagreement within the government on whether to pursue an Iraqi nationalist or Pan-Arabist agenda, eventually resulted in the bloody overthrowing of the Qassim regime in February 1963, also known as the Ramadan Revolution.
In order to appease these elements, loyalties of communalism and sectarianism were thus restored under Arif's presidency, as well as the political power of Sunni Arab nationalists.
[8] By doing this, Iraq developed into a welfare state: citizens throughout the country benefitted from economic advancement, rising incomes and social mobility, regardless of their ethnic, tribal or religious background.
[16] In line with its nationalist nature, the Ba’ath party managed to include different ethnic and religious groups in their governmental system after 1968.
Although the Ba'ath propagated the abolishment of sectarian ideologies and the inclusion of different sects in the military and other governmental institutions, by 1977 only Sunni tribal figures close to Hussein maintained positions in the Revolutionary Command Council, the highest form of authority.
[21] An example of clear violent sectarian opposition to such policies is the Second Iraqi-Kurdish War which took place in 1974 and 1975, when different Kurdish rebel groups unsuccessfully tried to gain independence in Northern Iraq by initiating riots.
[15][24] While the Ba'ath thus propagated national identity and included different ethnic and religious groups in the government, the party was also involved in constructing a tense atmosphere where there was no room for disloyalty or opposition.
[25][26] Under Hussein's rule, the system in which citizens, organizations, and parties were monitored intensified in order to prevent losing political dominance over Iraq.
For example, Kurdish, Shi'ite, and Iranian citizens were being deported out of Iraq with the motivation of being foreigners, which was often referred to as an act of sectarian cleansing at that time.
In 1979 the Iranian Revolution took place under the leadership of Shi'ite Grand Ayatollah Ruhollah Khomeini when he ousted the Pahlavi dynasty and paved the way for the establishment of the Islamic Republic of Iran.
Khomeini started a propaganda campaign aimed at Shi'ites in Iraq encouraging them to follow the Khomeinist ideology and to revolt against the Sunni dominated regime of Hussein in order to eventually overthrow it.
[38] In addition, many Shi'ite soldiers, officers, and citizens fled the country and sought refuge elsewhere, primarily in Iran and Alawite-dominated Ba'athist Syria.
[39] The Ba’ath regime punished these activist groups in northern Iraq by the use of extensive violence in the Al-Anfal Campaign at the end of the 1980s.
This use of extreme violence caused a high number of casualties estimated to be around 150,000 to 200,000 deaths and echoed further into the Kurdish community, contributing to a stronger sentiment of sectarian division.
[31] The rebels were mainly Shi'ite Arabs and Kurds who attacked the existing political power and their social exclusion under Ba’ath rule.
[31] As researcher and journalist Khalil Osman describes the uprisings:[42] The rebellion in southern Iraq was marked by a vigorous assertion of Shi’ite identity, featuring overtly Shi’ite religious symbolism and rhetoric.… But the passionate and strident assertion of Shi’ite identity vis-à-vis the despotic Ba’athist state gave rise to fears and feelings of exclusion among Sunnis, which resulted in their loss of sympathy for the rebellion.The uprisings were eventually suppressed by the use of brutal force and extensive violence by the regime such as mass executions of rebels.
[46][47] Besides different assassinations on influential political and religious figures, widespread sectarian violence in Iraq only erupted again after the removal of Hussein from office in 2003 following the U.S.-led invasion.
First of all, the Coalition Provisional Authority (CPA), under leadership of Paul Bremer, started a campaign of de-Ba'athification and dissolved the Iraqi military and security.
The new Iraqi Governing Council (ICG) came to be made up according to the country's demographics: 13 Shi'i, 5 Sunni Arabs, 5 Kurds, 1 Christian and 1 Turkman.
[51] In their rejection of the new political order, most Sunnis decided not to vote in the January 2005 parliamentary elections which resulted in their disenfranchisement in the newly formed government.
[52] Instead, the United Iraqi Alliance, made up of the two Shi'i parties Supreme Council for the Islamic Revolution in Iraq (SCIRI) and Da'wa, obtained a major victory.
[63] Besides sectarian killings by death squads, the violence also included kidnappings for ransom payments and torture in secret detention centres ran by militias.