As a sunni I believe that Ali was a righteous caliph & ameerulmomineen at the time of his rule.
Thus his position was legitimate vs those who rebelled.
I will post part of an ibadhi sect article regarding the people of nahrawan during Ali's rule.
The aim is not too promote its contents, but merely to highlight this alternate view of history shared by a section of the muslim ummah known today as ibadhi's who mainly reside in Oman & parts of north africa.
The shia always play the victim card & how they were persecuted throughout history.
Here, we see one of the earliest events of a historical narrative of a massacre by the shia of Ali.
As I said, this is the ibadhi narrative & not the sunni one.
Here it is:
The Shi‘a who surrounded Ali were anxious, in their efforts to create their state, lest the people of Nahrawan should establish relations with the rest of the people and convince them with arguments and proof that the acceptance of arbitration had been a political mistake, that Ali’s caliphacy (after the arbitration and his removal from office) was no longer valid, that the oath of allegiance to him was no longer binding, and that the real caliph was Abdullah ibn Wahb Al-Rasibi, who was given the oath of allegiance by a good number of Muslims. The Shi‘a feared that those at Nahrawan would establish contact with the people, and it was for this reason that they wanted to eradicate their opinions, lest they be disseminated among people, who might then understand them and become convinced of their validity.
It was only possible to eradicate these opinions by eradicating the people who held them. Had Ali hesitated in this matter and avoided bloodshed, everything would have been lost. Thus, he had to be pushed to take this decisive and crucial step by any means possible.
They were able to convince him through Al-Ash‘ath. He took the step, initiated the fight and eradicated the people of Nahrawan. But he was not able to eradicate the idea that they proclaimed, that idea which has filtered through with its truth and reality into the minds of many, until it became a principle that its upholders defend with patience, courage and resilience.
4000 of Al-Muhakkimah, were killed in Al-Nahrawan Battle, including the Imam of the people of Nahrawan, Abdullah ibn Wahb Al-Rasibi. Ibadhi sources indicate that most of the martyrs were jurists, Quran reciters and people of hounor in religion and opinion. Among them were Owais Al-Qurni, Hurqus ibn Zuhair Al-Sa'di, and other best companions, may Allah be pleased with them.