Thesis: Whether it is religion or ideology, it has always played an influential role in the making of empires.
Explanation:
The reconquest of Muslim Spain by the Catholics started around the turn of the new milennium. This was a joint effort by Spanish kingdoms (state) and the catholic church. Once succeded the Spanish, united by religion, drove the Jews out, as other European counties had done before them.
The Muslim resurgence between the 14th and the 16 century can likewise be seen as religion coinciding with state expansion. The Ottoman Empire in East Europe and Minor Asia is one example but also the Mughal Empire in India and Persia were important in spreading the Muslim faith all the way to China and Indonesia. So for a short time these three Muslim empires controlled a territory from Morocco in the West to the borders of China in the East. Not for long because the clash between Sunnite Turkey and Shi'ite Persia drove a wedge into the Muslim world.
It is safe to say that Muslim (land) hegemony ended when military hegemony was passing to the sea and to the peoples who knew how to master and exploit it.
