When the major city of Mosul was occupied by the paramilitary forces of the Islamic State group (IS), Tehran was alarmed even before Washington. IS’ quick attacks and unexpected expansion confused the leaders and politicians of neighboring countries for weeks. There were many discussions regarding how Iran might respond to the crisis in Iraq. However, as always, Tehran was able formulate its own military and security strategies, and by utilizing the Quds Force, a special unit of Iran's Revolutionary Guard Corps (IRGC), was able block the progress of the forces of Abu Bakr al-Baghdadi.

In this case, Iran extended its policy of taking an advisory role, as well as providing support for Shiite groups from Syria to Iraq. The IRGC’s Quds Force is in charge of protecting the military and security interests of Iran outside its borders. Quds Force head Maj.-Gen. Qasem Soleimani showed Iran’s determination in fighting against IS by being personally present in Iraq.

After Saddam Hussein was toppled in 2003, in an act of rivalry with the United States, Iran quickly started to form paramilitary groups in Iraq and also started to support those Iraqi politicians who had ties to Iran. Several groups including the Mahdi Army, which is connected to Muqtada al-Sadr, Asa'ib Ahl al-Haq, Liwa'a Zulfiqar, Kata'ib Sayyid al-Shuhada, Kata'ib Hezbollah, Liwa'a 'Ammar Ibn Yasir and Munadhamat Badr were formed in Iraq with the support of Tehran, especially after the United States withdrew its forces. The newest of these is Saraya al-Khorasani.

Saraya al-Khorasani means “Khorasani Brigades,” or “forces obedient to the Seyyed of Khorasan.” For the Shiites, who have ties with Iran, “Seyyed Khorasani” is a reference to Supreme Leader Ayatollah Khamenei. One of the features that distinguish Saraya al-Khorasani from other Shiite groups is the logo the group has chosen for itself. In a rather unprecedented move, Saraya al-Khorasani’s official logo is identical to that of the IRGC. From the very beginning, Saraya al-Khorasani was made up of Shiites from southern and central Iraq and its main goal was fighting IS. Another element that distinguishes this group from other Shiite groups was its rather quick formation process. In two months’ time, Saraya al-Khorasani was able to gather forces and organize various military operations.