On October 9, the Iraqi government headed by Prime Minister Mustafa al-Kadhimi and the semi-autonomous Kurdistan Regional Government (KRG) signed the “Sinjar Agreement” to normalize the situation in the war-torn district of Sinjar in northern Iraq. The agreement stated that only Iraqi federal forces should operate in Sinjar and all other armed groups must leave the town. It also gave the KRG a say on establishing a new local government, including appointing a new mayor, and planning and running reconstruction efforts in Sinjar, including related budgetary matters (Rudaw, October 10).
Both the Iraqi government and KRG were struggling to extend their authority into Sinjar town and the larger district of the same name. Since 2017, Sinjar district has been under the control of groups affiliated with the Iranian-backed Popular Mobilization Units (PMU) and Kurdistan Workers’ Party (PKK). Both the PMU and PKK obviously did not welcome the recent Sinjar Agreement between the Iraqi government and KRG, and some PMU and PKK leaders condemned it (Alforat News, October 11; pleasebaghdadtoday.news, October 10).
Nevertheless, on December 1, Iraqi forces entered Sinjar and started taking over positions previously occupied by the PMU and PKK-affiliated groups (Nina News. December 2). The takeover occurred after a series of side negotiations between the Iraqi government, PMU, and PKK that spared Sinjar of renewed military confrontations once Iraqi government forces deployed to Sinjar. However, the situation remains volatile. Some reports suggest that the PMU and PKK were not committed to either a full withdrawal from Sinjar or compliance with Iraqi government’s authority in Sinjar (Al Araby, November 29).
Sinjar’s Strategic Location
Sinjar is a strategic location for various armed groups and regional powers. For Iran and its Iraqi proxy militias in the PMU, Sinjar is a main crossing between Iraq and Syria. The US, therefore, welcomed the Sinjar Agreement in the hope that restoring Iraqi government and KRG authority in Sinjar would curtail Iranian influence.
Although Iran’s Iraqi proxy militias in the PMU objected to the agreement, Tehran was not quick to condemn it either. Iran has other means of influence in Iraq and might wait to see how events in Sinjar unfold. Similarly, for the PKK, Sinjar has represented the eastern flank of territories controlled by the Kurdish-led Syrian Democratic Forces (SDF). The main SDF component is the People’s Protection Units (YPG), which is a PKK affiliate.
Turkey welcomed the Sinjar Agreement because it reduced YPG/PKK influence, but Turkey will closely track its implementation. Turkey considers the PKK as an existential threat to its national security and previously threatened it would invade Sinjar to drive out the PKK if Iraq was not willing to do so (turkeyalaan.net, October 11). It should be noted that the Sinjar Agreement was preceded by a significant improvement in Turkish relations with Iran and a higher degree of coordination of their activities not only in Iraq, but also in Syria (thenewkhalij.com, June 19).
The Sinjar Massacre’s Legacy
Sinjar was the epicenter of Islamic State (IS)’s campaign against the Yazidi community in the summer of 2014. Thousands of Yazidis suffered during mass killings and enslavement by IS, which considered Yazidis to be infidels. Yazidi women and girls especially suffered because IS captured thousands of them as sex slaves (sabaya).  Sinjar had fallen to IS after the KRG’s Kurdish forces (peshmerga) fled IS advances, much like the Iraqi army had done in Mosul and other cities. Yazidi civilians who managed to flee Sinjar found their only refuge in the nearby Sinjar Mountain, where PKK fighters were the only force that seemed willing and able to resist IS’ major advances (noonpost.com, August 26).
The following months after IS’ invasion of Sinjar saw increased fighting between IS and the PKK and its affiliates in Syria and Sinjar. In 2015, the PKK then played a key role in the campaign to retake Sinjar from IS alongside the KRG’s peshmerga, Iraqi forces, and PMU. In October 2017, relations between the Iraqi government then headed by Prime Minister Haider al-Abadi and the KRG deteriorated after the latter insisted on holding a referendum on independence. The referendum was also condemned by Turkey and Iran, which both have their own Kurdish minorities. In retaliation against the KRG for their referendum, the al-Abadi government ordered Iraqi forces, who were alongside the PMU, to expel the peshmerga from Sinjar, as well as other larger disputed areas in Iraq, including Kirkuk (Al Arab, October 18, 2017).
After the KRG’s peshmerga was expelled from Sinjar, the power of PKK-affiliated groups in Sinjar increased, as they now shared control of Sinjar with the PMU. The PKK had already worked to build affiliated militias comprised of Yazidi locals. The largest among those is the Sinjar Resistance Units (YPS), which is estimated to have at least 7,000 fighters and was the first militia formed by the PKK in Sinjar in 2014 to combat IS. The other large PKK-affiliated militia is the Ezidkhan Protection Force (EPF), whose leader is Haider Shasho. It is believed to have more than 5,000 members. Besides the YPS and EPF, other smaller Yazidi groups exist, including the National Yazidi Front, which is based in the town of Kojo to the south of Sinjar, and the Lalish Battalion (Al Jazeera, April 23, 2019).
PMU and PKK’s Regional Rivals
In the face of their common regional foes, including the KRG and Turkey, relations between the PMU and PKK were bolstered. A deal between the PMU and PKK was, therefore, designed by PMU leader, Abu Mahdi al-Muhandis, in 2019 before al-Muhandis was killed in January alongside Iranian General Qasem Soleimani in a U.S. airstrike outside Baghdad international airport. This deal paved the way for YPS and other Sinjar-based PKK-affiliated groups to join the payroll of PMU, which is funded by the federal government in Baghdad (Al Jazeera, April 23, 2019). 
Yet, other more recent developments since 2019 led to the Sinjar Agreement. Prime Minister Mustafa al-Kadhimi assumed office in May 2020 and seemed willing to try to check the PMU’s power.  Additionally, relations between the Iraqi government and the KRG have significantly improved since the 2017 referendum crisis. After the 2018 Iraqi parliamentary elections, the Kurds reclaimed the role they played in Iraqi politics since 2003 and enhanced their position in the federal government. Unlike al-Abadi, the current Iraqi prime minister, al-Kadhimi, has been friendlier with the KRG.
In his previous position as head of the Iraqi Intelligence Service (Jihaz al-Mukhabarat), al-Kadhimi reportedly even built a good working relationship with his Turkish counterpart, Hakan Fidan, who reportedly made a secret visit to Baghdad in June and met senior Iraqi officials (alarab.co.uk, June 13). Turkey is the main backer of the Kurdistan Democratic Party (KDP) led by the Barzani family, which is the largest party in the KRG. In Sinjar, the goal of the KRG was to regain at least part of its influence. Although the Sinjar Agreement does not allow the peshmerga to come back to Sinjar, it does give the KRG, and especially the KDP, an avenue to regain some of their influence in Sinjar. Thus, Turkey also gains more influence in Sinjar via the KDP as a result of the Sinjar Agreement, but it was still more important for Turkey to remove the PKK from Sinjar due to its geographic proximity to Turkey.
The Kurds are often mistakenly viewed in the international media as a monolithic group. In reality, however, rival Kurdish groups have differences in their positions and alliances. The situation in Sinjar is a microcosm of these dynamics. After the U.S.-led invasion of Iraq in 2003, Sinjar came under the control of the KDP, which also restored some of its power in the area after IS was driven out in 2015. Mahma Khalil, a local Yazidi politician and member of the KDP, for example, became Sinjar’s mayor. By that time, the PKK and PMU had significant power and influence in Sinjar as well. The 2017 rift between the Iraqi government and KRG subsequently led to the removal of not only the peshmerga from Sinjar, but also the KDP-led local administration and Mahma Khalil, who went into exile in areas controlled by the KDP. The PKK, for its part, moved in to support the appointment of Fahad Hamed Omar as Sinjar’s mayor. This gave the PKK greater influence on Sinjar’s administration.
Sinjar has become the flashpoint of a larger and long-term conflict between the PKK and the KDP. In early November, for example, the PKK launched attacks on the KDP peshmerga, which is under the KRG, in northern Iraq that killed one and injured eight Iraqi Kurdish peshmerga fighters (Aawsat, November 6). KDP leader Massoud Barzani condemned the PKK attacks and threatened that he might reconsider his position of opposing intra-Kurdish infighting (Nas News, November 2).
However, clashes between the Kurds has been far from taboo. The Turkish-supported KDP, for example, joined forces with Turkey in several campaigns against the PKK in Iraq in the 1990s and early 2000s.  However, since 2003, the KDP and PKK have avoided direct military confrontations. 
The PKK, meanwhile, also fought Iraqi federal forces in March (Al Arabiya, March 18, 2019). This was because confronting the PKK, especially in Sinjar, became a priority for both Iraqi federal government forces and the KRG by that time as a result of Turkish pressure that has always loomed in the background. Turkey has offered Iraq its support to expel the PKK from Sinjar, but President Recep Tayyip Erdogan threatened in 2018 that his forces would invade Sinjar to drive out the PKK if Iraq took no action (Al Araby, March 19, 2018). Thus, Iraq was compelled to take action in Sinjar, and the PKK responded.
PKK, PMU and Sunni Arabs’ Perspectives Under the Specter of IS
The PKK might prefer not to challenge the initial implementation of the Sinjar Agreement militarily, but only on the local administrative level. Many in the Yazidi community resent the KRG and remember how its forces retreated from Sinjar without protection when IS invaded in the summer of 2014. On the contrary, Yazidis embraced the PKK because it provided them with the only refuge at the darkest hour in their history. 
The PMU was also not pleased with the Sinjar Agreement. The leader of Asa’ib Ahl al-Haq (League of the Righteous—AAH), Qais al-Khazali, leads an almost entirely Shia group. However, he has based his argument against the Sinjar Agreement on the grounds that it is against the interest of the Yazidis (alquds.co.uk, October 11).
That the Sinjar Agreement was opposed by Sunni Arabs in Ninawa was also notable. They allege the Sinjar Agreement ignores their demands and the current situation (iqiraq.news, October 11). This is because when the Yazidis returned to Sinjar in 2015—armed and supported by the PKK and PMU—almost all Sunni Arabs from the area became displaced. The Yazidis, meanwhile, accuse those Sunni tribes of having embraced IS. Acts of revenge took place against Sunnis, who obviously deny the accusation of having supported IS. That dimension of the conflict indicates how complex the situation is in and around Sinjar.
The UN, meanwhile, welcomed the Sinjar Agreement as a means to normalize the situation on the ground in order to pave the way for the return of displaced people. However, that goal will take much more than a single agreement. Increased disenfranchisement and suffering for the Sunni displaced people always keeps the door open for IS to exploit the situation in Sinjar and beyond.
The Turkey-Iran Tango
The mutual PKK and PMU influences and interests in Sinjar makes it one of the most dynamic areas in Iraq today. Both the PKK and PMU have built relations with the local Yazidi community in a way that would make it difficult for the Iraqi government and KRG to restore full control of the area. However, much will depend on Iran’s strategic decisions. The Sinjar Agreement was facilitated by recent coordination between Turkey and Iran. The latter shows some understanding for Turkey’s concerns about the PKK. And as Turkey launched a campaign against PKK positions inside Iraq in the summer of 2020, Iran also attacked its own Kurdish PKK-linked rebels inside of Iraq called The Kurdistan Free Life Party, or PJAK (Aawsat, June 18).
While Turkey has historically supported the KDP in the KRG, Iran has supported its rival, the Patriotic Union of Kurdistan (PUK), which is led by the Talibani family. The usual friendly position of Iran and the PUK towards the PKK seems to have changed recently in favor of greater coordination with Turkey. Sinjar will, therefore, be the place to test that trend.
The Iranian-backed PMU and PUK position in Sinjar will depend on how much Iran is willing to concede to Turkey. Iran is unlikely to easily abandon Sinjar as it remains one of its crossings between Iraq and Syria. But Iran has clearly chosen to cooperate with Turkey as part of a larger strategy that involves the two countries’ agreements in Syria, which is another country where they have conflicting interests and have supported opposing parties.
For now, all parties are seemingly consolidating their positions in Sinjar, while closely monitoring developments in Syria, and also awaiting the possible changes in strategy that the incoming U.S. administration may introduce in 2021.
 Under IS’s strict interpretation of Islamic sharia law, the Yazidi faith is not recognized as a monotheistic faith. Unlike Jews and Christians, who could live as second-class citizens under Islamic rule after paying a protection tax called jizya, Yazidis were considered infidels, or kafir. The IS ruling on the Yazidis when they were captured at war was to kill all adult males and enslave all women and children.
 The PMU is dominated by Iranian-backed Shia militias, but it is also an official part of the Iraqi armed forces.
 Al-Kadhimi assumed office in May after bloody street protests in Baghdad and the Shia south of Iraq against Iranian-backed political parties. Iran did not oppose the secular Shia politician, al-Khadimi. Although al-Khadimi has not delivered on his promises to fully take responsibility for Iraqi security and control Iranian-backed militias, he has shown that he is willing at least to try to fulfill that difficult and complicated mission.
 Barzani’s party and its main rival in Iraqi Kurdistan, the PUK, which is led by the family of late former Iraqi president Jalal Talabani, engaged in years of civil war between 1993 and 1998. This occurred after the Kurdistan region fell outside the authority of Baghdad and under the U.S. and Western protection of a no-fly zone. Thousands were killed in the conflict that only ended when Barzani and Talabani signed a U.S.-mediated peace agreement on September 17, 1998 at the State Department in Washington, D.C. alongside then-Secretary of State Madeleine Albright.
 Since 2003, the KDP and PKK have avoided direct major military confrontations. However, fighting between the two groups has become more frequent recently, including as this article went to press. Both groups blame each other for the violence.
 Author’s interview with a Yazidi journalist, who preferred to remain anonymous on December 2, 2020.