A medieval historian has told the trial of Lisa Smith, a former soldier who denies membership of Isis, that for many the Islamic State created by terrorist leader Abu Bakr al-Baghdadi provided simple answers to life's questions and was considered legitimate by respected religious scholars.
Professor Hugh Kennedy also said that it is possible for a person to believe in the caliphate - an Islamic state that has existed in different places since the seventh century - but not believe in the ideology of Isis, the terrorist organisation.
The professor said the Isis message was persuasive for some, and it used a selective representation of the religion's history to justify barbarism.
While he accepted there were many Islamic scholars who denounced al-Baghdadi, he said there were other "respected voices" who saw his caliphate as legitimate and who could find justifications for what it did in Islamic texts.
For many Muslims, he said the caliphate offered a "new beginning" and a return to values that seemed to have been lost.
Professor Kennedy was called by Ms Smith's defence lawyers after the prosecution completed its evidence last week.
Ms Smith (40), from Dundalk, Co Louth, an Islamic convert, travelled to Syria in 2015 after al-Baghdadi called on all Muslims to travel to the Islamic State he had created.
She has pleaded not guilty to membership of an unlawful terrorist group, Islamic State, between October 28th, 2015 and December 1st, 2019.
She has also pleaded not guilty to financing terrorism by sending €800 in assistance, via a Western Union money transfer, to a named man on May 6th, 2015.
Appointing a caliphate
Professor Kennedy told Michael O'Higgins SC, for Ms Smith, that he is a professor at the University of London and wrote a book on the history of the caliphate from the death of Mohammad in 632CE until the 11th century.
He said that period may seem ancient, but it is relevant to modern discussions on the legitimacy of the Islamic State caliphate.
Al-Baghdadi, he said, claimed justification for his caliphate by looking at what happened during the first four centuries of the religion and by using the imagery of that era.
The Islamic State, he said, was "deeply anchored in the Quran and Hadiths which form the basis on which all Muslims agree is the foundation of their faith".
The Quran, he said, is considered the literal truth by Muslims and the Hadiths are the reputed utterances of the prophet Mohammad.
There are, he said, disputes about the Hadiths and Muslims can believe different things.
The criteria for appointing a caliphate, he said, are "by no means clear or universally held".
Shia Muslims, he said, believe that the leader of a caliphate - the caliph - must be a descendant of Mohammad while Sunnis believe that he must come from the prophet's tribe, the Quraysh.
There have been various caliphates over the centuries, he said, including under the Ottoman Empire, although the sultans tended not to use that title.
In the 20th century, he said the idea had largely become irrelevant until al-Baghdadi's announcement in 2014.
He said it would be difficult to prove that al-Baghdadi came from the Quraysh tribe, but it is not implausible given that a huge number of people could claim to be members of that tribe.
While many rejected al-Baghdadi as a caliph, there was a significant number of people looking for the new caliphate and willing to accept al-Baghdadi, he said.
When Mr O'Higgins asked if there were "respectable voices" saying the caliphate was legitimate, he responded: "Yes. The criteria are so vague that evidence could be found to support it.
"For a good number of Muslims the caliphate seemed to offer an opportunity for the revival of the power and prestige of the Islamic community in the world and the going back to the original commitment and enthusiasm which was important for people who thought that had been lost."
He said Muslims from all over the world thought the caliphate offered a "new beginning".
An eternity in hell fire
The professor agreed that Isis also stated that there was a religious obligation on Muslims to travel to the Islamic State and that failure to do so would result in an eternity in hell fire.
The witness agreed with Sean Gillane SC, for the Director of Public Prosecutions, that the history of the caliphate is rich and varied, full of colour and texture, but that it can also be manipulated and distorted by ideologues for their own purposes.
He added that the caliphate and the Islamic State are not necessarily the same thing.
"You can believe in the caliphate without believing in the ideology of Isis," he said.
Isis, he said, used online magazines such as Dabiq to present themselves as learned in a way that most Muslims are not and to tell others to follow their example.
Their writings, he said, were full of references to the early texts but were often misinterpreted or distorted.
The Quran, he said, is a "wonderful text" but it is not consistent or methodical, and it is a prophetic rather than legal text.
Muslims continue to find new ways to read and understand it, he said. Mr Gillane put it to him that, in 2015, hundreds of Islamic scholars wrote an open letter denouncing al-Baghdadi and pointing out parts of the Quran that showed his methods were wrong.
Professor Kennedy said there were hostile comments from Muslims towards Isis but "as in so many things you can find contrary examples".
He said there were "learned voices on both sides of the community".
Justification of barbarism
Professor Kennedy said it is difficult for non-Muslims to realise how many different opinions there are in Islam.
While only a minority support the kinds of things al-Baghdadi was doing, he said they do represent an "established strand" within the religion.
Mr Gillane asked if Professor Kennedy would "put trust" in someone writing for an Isis propaganda magazine like Dabiq.
Professor Kennedy replied: "It is not for us to put trust in it because we are not Muslims searching for guidance on how to be a good Muslim... For some, what al-Baghdadi was saying seemed to be a way forward and a way out of the problems in the Muslim community and back to a pure and exhilarating past where the course of right actions was clear."
He said Isis took certain aspects of the religion's history and exaggerated them to make their point and to justify barbarism.
"If you look hard enough you can find a way to justify anything," he said.
Looking back on the rule of different caliphs, he said, you can find some that were aggressive and others who were peaceful and open to new ideas.
Under re-examination Professor Kennedy said Isis propaganda was persuasive, used selective ancient texts and spoke to people who "wanted straightforward answers. It gave certainty which was important for people who wanted simple answers to life's questions."
Mr Gillane will deliver his closing speech to the three-judge non-jury court on Tuesday. Mr Justice Tony Hunt is presiding.