Harakat Hezbollah al-Nujaba, officially the 12th Brigade, is a radical Iraqi Shi'ite paramilitary group that is especially active in Syria and Iraq. It was established in 2013 by Akram al-Kaabi to support Bashar al-Assad in Syria against Islamist rebels. The group is supported by the IRGC's Quds Force, which provides the funding, weapons, and training of its members.

The Axis of Resistance is an informal Iranian-led political and military coalition in West Asia and North Africa. It most notably includes,Islamic Resistance in Iraq, the Syrian government, the Lebanese political party and militant group Hezbollah, the Yemeni political and military organization Ansar Allah, and a variety of Palestinian militant groups. The various actions of members of this axis reflect their domestic interests while serving the broader goal of complicating Israel's attacks and imposing a cost on the United States to support Israel. The axis became the main fighters against ISIS, after the group took over Syria and Iraq in 2014.