From all of my contacts on the ground, in the Middle East and in Syria, there seems no doubt that ISIS was funded, armed and supported by Saudi Arabia, Qatar and the US government, to topple the secular government of Assad of Syria.
There is also no doubt that the vast majority of Christians in Syria support Assad. His and his father's government have steadfastly protected Christians and suppressed the radical Islamicists Jihadists in Syria.
Six percent of the population of Syria are Christians, one of the highest percentages in the Middle East. I have seen photographs of churches packed with Syrian soldiers and large crowds of Christians walking with crosses and pictures of Assad. I have also received letters from church leaders in Syria, supporting Assad as their protector from the radical Islamic Jihadists. There has also been a number of films of Assad and his wife visiting churches and celebrating Christmas with Christians in Aleppo, since its liberation from the ISIS terror.