Starting in 1918, the British and French began to divide up the Ottoman Empire, drawing the boundaries of both present day Syria and Iraq. Good Imperialists that they were, they made sure to draw the borders so that each country would have at least 2 to 3 rival ethnic groups who could be pitted one against the other against the other thus facilitating their becoming a colony. similarly to what the British had been able to do in the 19th Century. on the Indian sub-continent.
The Caliphate to which ISIS alludes came into being in the 8th and 9th Centuries under Muslim Arabs who conquered large swathes of territory including all of present day Arabia and the Levant, including present day Syria and Iraq. Most of the land was incorporated into the Ottoman Empire starting in the 11th Century.
ISIS signalled that it wanted to return to a Syria and Iraq as it existed before the Ottoman Empire, and before the British and the French drew the boundaries. By changing its name to ISIL, it was already signaling that it had already expanded its geographic scope of action.
As the Centennial Year of 2018 approaches, be sure to celebrate the birth of ISIS on November 11th of that year.