The formation of the Northern Sun Battalion was announced by Mohammed Hammou, a brigadier general who defected from the Syrian Armed Forces, in the Manbij countryside on 16 April 2014. Less than a week later, several other small groups and individuals joined the battalion, including Abu Layla and several other commanders from the Kurdish Front and the Free Syria Brigade's eastern branch. On 3 May 2015, some of former members of the northern branches of the Hazzm Movement, and the Syrian Revolutionaries Front along with Jabhat al-Akrad, the Dawn of Freedom Brigades main component group the Northern Sun Battalion and smaller FSA groups formed the Army of Revolutionaries. Many of the northern members of the Syrian Revolutionaries Front and Hazzm Movement also joined the Levant Front. In October 2015 it became part of the Syrian Democratic Forces. Subsequently, the Dawn of Freedom Brigades went defunct. In November, the battalion participated in the Syrian Democratic Force's al-Hawl offensive, and according to commander-in-chief Adnan al-Ahmad was committed to pushing ISIL out of al-Shaddadah and Raqqa, as well as from Jarablus, the Tishrin Dam and Manbij. When the Manbij Military Council was set up on 3 April 2016, the battalion's second-in-command, Adnan Abu-Amjad, was made the council's general commander. In course of the following Manbij offensive, one of the Northern Sun Battalion's most prominent commanders was killed: Abu Layla died on the 5th of June 2016, after being shot in the head by an Islamic State sniper on Friday June third, in the countryside south of Manbij, Syria. He had previously been evacuated by a US military helicopter to a hospital in Sulaymaniyah, Iraqi Kurdistan, but doctors were unable to remove a bullet to the head and prevent internal bleeding to the brain. On 28 August 2017, pro-Syrian government media reported that Ibrahim al-Banawi, commander of the Northern Sun Battalion's Soldiers of the Two Holy Mosques Brigade, had defected to the Syrian Army in the southern Raqqa countryside; this was proven to be false, as Ibrahim was still with the Northern Sun Battalion in January 2018. On 29 August 2017, Adnan Abu Amjad, former deputy commander of the Northern Sun Battalion and the general commander of the Manbij Military Council, was killed in action during the Battle of Raqqa. On 17 September 2017, Muhammad Mustafa Ali, also known by his nom de guerre "Abu Adel", the general commander of the Northern Sun Battalion, was appointed the general commander of the Manbij Military Council as the successor of Adnan Abu Amjad.
On 15 March 2017, a video surfaced that showed members of the Northern Sun Battalion torturing an ISIL fighter, who had been captured while planting mines. One of these mines had killed nine fighters of the battalion, leading five others to take revenge on the ISIL militant. The Manbij Military Council condemned the act, and announced that the involved Northern Sun Battalion fighters would be held for trial for violating the Geneva Conventions. The five accused were subsequently arrested on 17 March.