Samarra in the context of "Tin-glazed pottery"

The Tigris (/ˈtaɪɡrɪs/ TY-griss; see below) is the eastern of the two great rivers that define Mesopotamia, the other being the Euphrates. The river flows south from the mountains of the Armenian Highlands through the Syrian and Arabian Deserts, before merging with the Euphrates and reaching to the Persian Gulf.

The Tigris passes through historical cities like Mosul, Tikrit, Samarra, and Baghdad. It is also home to archaeological sites and ancient religious communities, including the Mandaeans, who use it for baptism. In ancient times, the Tigris nurtured the Assyrian Empire, with remnants like the relief of King Tiglath-Pileser.

Upper Mesopotamia constitutes the uplands and great outwash plain of northwestern Iraq, northeastern Syria and southeastern Turkey, in the northern Middle East. Since the early Muslim conquests of the mid-7th century, the region has been known by the traditional Arabic name of al-Jazira (Arabic: الجزيرة "the island", also transliterated Djazirah, Djezirah, Jazirah) and the Syriac variant Gāzartā or Gozarto (ܓܙܪܬܐ). The Euphrates and Tigris rivers transform Mesopotamia into almost an island, as they are joined together at the Shatt al-Arab in the Basra Governorate of Iraq, and their sources in eastern Turkey are in close proximity.

The region extends south from the mountains of Anatolia, east from the hills on the left bank of the Euphrates river, west from the mountains on the right bank of the Tigris river and includes the Sinjar plain. It extends down the Tigris to Samarra and down the Euphrates to Hit, Iraq. The Khabur runs for over 400 km (250 mi) across the plain, from Turkey in the north, feeding into the Euphrates.

Kufa (Arabic: الْكُوفَة "al-Kūfah"), also spelled Kufah, is a city in Iraq, about 170 kilometres (110 mi) south of Baghdad, and 10 kilometres (6.2 mi) northeast of Najaf. It is located on the banks of the Euphrates River. The estimated population in 2003 was 110,000.

Along with Samarra, Karbala, Kadhimiya and Najaf, Kufa is one of five Iraqi cities that are of great importance to Shi'ite Muslims. The city was founded in 638 CE (17 Hijrah) during the reign of the second Rashidun Caliph, Umar ibn Al-Khattab, and it was the final capital of the last Rashidun Caliph, Ali ibn Abi Talib. Kufa was also the founding capital of the Abbasid Caliphate. During the Islamic Golden Age it was home to the grammarians of Kufa. Kufic script is named for the city.

Ali ibn Muhammad al-Hadi (Arabic: عَلي إبن مُحَمَّد الهادي النَّقي‎; c. 7 March 828 – c. 21 June 868) was a descendant of the Islamic prophet Muhammad and the tenth Imam in Twelver Shia, succeeding his father, Muhammad al-Jawad (d. 835). Born in Medina in 828, Ali is known with the titles al-Hādī (Arabic: الهادي, lit. 'the guide') and al-Naqī (Arabic: النقي, lit. 'the distinguished'). After the death of his father in 835, most followers of al-Jawad readily accepted the imamate of Ali, who was still a child at the time. Drawing parallels with the story of young Jesus in the Quran, Twelver sources attribute an exceptional innate knowledge to Ali which qualified him for the imamate despite his young age.

As with most of his predecessors, Ali al-Hadi kept aloof from politics until he was summoned around 848 from Medina to the capital Samarra by the Abbasid caliph al-Mutawakkil (r. 847–861), known for his hostility towards Shias. There al-Hadi was held under close surveillance until his death in 868 during the caliphate of the Abbasid al-Mu'tazz (r. 866–869). Still, he managed to communicate with an underground network of representatives who organized the financial and religious affairs of the Shia community on his behalf. Most Shia sources hold the Abbasids responsible for his death at the age of about forty through poison, with the notable exception of al-Shaykh al-Mufid (d. 1022). His image in Twelver sources is that of a pacifist, persecuted Imam who endured numerous attempts by members of the Abbasid court to humiliate and dishonor him. These sources also allege more serious incidents of house search, temporary imprisonment, and even murder plots against al-Hadi.

Upper Mesopotamia constitutes the uplands and great outwash plain of northwestern Iraq, northeastern Syria and southeastern Turkey, in the northern Middle East. Since the early Muslim conquests of the mid-7th century, the region has been known by the traditional Arabic name of al-Jazira (Arabic: الجزيرة, lit. 'the island', also transliterated Djazirah, Djezirah, Jazirah) and the Syriac variant Gāzartā or Gozarto (ܓܙܪܬܐ). The Euphrates and Tigris rivers transform Mesopotamia into almost an island, as they are joined together at the Shatt al-Arab in the Basra Governorate of Iraq, and their sources in eastern Turkey are in close proximity.

The region extends south from the mountains of Anatolia, east from the hills on the left bank of the Euphrates river, west from the mountains on the right bank of the Tigris river and includes the Sinjar plain. It extends down the Tigris to Samarra and down the Euphrates to Hit, Iraq. The Khabur runs for over 400 km (250 mi) across the plain, from Turkey in the north, feeding into the Euphrates.

In June 2014, the Islamic State (also known as ISIS or ISIL), which had controlled a large portion of Northeastern Syria at that time during the Syrian civil war, launched a full-scale invasion of Iraq, capturing a large swath of territory extending all the way from the Iraq–Syria border to the outskirts of the Iraqi capital city of Baghdad. The invasion came after months of clashes in Anbar province, where tribal groups, and some extremist factions—which had pledged allegiance to ISIL—had been fighting Iraqi government forces in the cities of Fallujah and Ramadi following a series of anti-government protests. The offensive led to the occupation of 40% of Iraq’s territory by the Islamic State, the collapse of several elements of the then-corrupt Iraqi Army and the genocides and mass killings of various religious groups, such as the Yazidis, Christians and Shia Muslims (who form a majority in the country). This event led to the intervention of Iran and the United States in assisting Iraq in its conflict with the Islamic State, with the latter providing assistance to both Iraqi and Kurdish forces.

The Islamic State of Iraq and the Levant and its allies captured several cities and surrounding territory, beginning with an attack on Samarra on 4 June, followed by the seizure of Mosul on 10 June, and Tikrit on 11 June. As Iraqi government forces fled south on 13 June, Kurdistan Regional Government force's took control of the oil hub of Kirkuk, part of the disputed territories of Northern Iraq.