Just in case, in later starts Saladin does exactly the same things as the Fatimids.
And the Pope usually replies with a Crusade for Andalusia.
With the Spanish kingdoms swearing fealty to the HRE.
Yes I'm mad.
In my Francia game, Saladin didn't expand that much. In fact, at 1380+, Kingdom of Jerusalem is still around, and even slightly bigger.
The Pope did call Crusades on Iberia a few times. Once, I grabbed Leon. Another time, HRE grabbed Mauritania, which by this time had large parts of Andalusia in it. Before that, despairing at how the Christian states cannot fend off the Muslims, I brought them under one roof.