The Kharijis (Khawarij) were mostly the ones that had left Ali’s army near Harura on the pretext that Ali was an ungodly caliph since he had accepted the arbitration.
After the arbitration, they denounced both Ali and Muawiyah and called them infidels. They chose their own leader named Abdullah bin Wahb and mustered a force of 4k men to march on Madinah and make it their seat of theocratic government.
They were repelled by Madinah Governor, they then marched towards the town of Nahrawan which they captured.
Most of them originally belonged to Bedouin tribes of Yemeni origin, especially of great Tamim tribe.
They were inspired by the Islamic principles of equality and fraternity and looked to the equalitarian, feudalistic tribal system of Umar.
They sought to preserve that against the emergent big feudalism of Umayyad in Syria or of Ali in Iraq. They believed that Ali or Muawiyah both strived to strengthen Quraishite aristocracy.
They wanted the system as it was in Abu Bakr or Umar’s time. They also thought Usman was rightly elected and followed Umar’s path but then fell victim to nepotism, for which he was rightly executed.
They had also accepted Ali’s election. But defected when he accepted the arbitration. They contended he wasn’t fit to be a caliph when he himself questioned God’s decision to elect him in first place. Therefore, he too should be deposed for his blasphemy.
Ali versus Kharijis
Ali again summoned a large force against Muawiyah and well on his way to Syria when he heard about the mistreatment that Kharijis were inflicting upon those who questioned their beliefs in Nahrawan.
They killed Abdullah bin Khabbad and his pregnant wife when Abdullah argued that Usman was killed unjustly.
Ali reached Nahrawan and defeated them there. All but seven escaped alive from the battlefield. The battle took place in 658 March.
After the victory the Caliph returned to Kufa to rest a bit. When he called his soldiers again for marching towards Syria, they seemed reluctant. They complained they were too tired of fighting and their weapons too were in bad condition. Ali stalled the plan for a while.
Loss of Egypt
We know how Qays had be called back by Ali due to Muawiyah’s conniving games. He was replaced by Muhammad bin Abu Bakr. The new governor was brave but not a good administration.
He adopted provocative policy towards pro-Usman faction. He asked them to either submit or leave the region. They didn’t revolt at that time but did so after the arbitration.
Muawiyah sent Amr there to support the revolt. He was promised governorship of Fustat by Muawiyah.
Thus Egypt was lost too. Amr again became the governor of Egypt. And he remained the chief for 8 years till his death.
Truce with Muawiyah: 660
It is to be noted that events in this heading are contested and conflicting.
Ali was too weak to continue hostilities with Muawiyah. It is said Ali and Muawiyah concluded a truce in 660 which didn’t last long.
Subsequently, Muawiyah assumed the title of Khalifa in Jerusalem. Ali again was to set out to challenge, but he was murdered and embraced martyrdom.
For complete Islamic history notes click here.