Vast numbers of troops were diverted into occupation armies, tasked with putting down rebellions in newly-captured provinces ranging from southern Spain to Libya, denying reinforcements to my exhausted Egyptian expedition.
I don’t remember the details of the campaign, only that it succeeded wildly… and left me massively overstretched. I would capture the Nile Delta, shatter Egypt’s strength, and then use the the Nile basin as as a launchpad for direct attacks on the Byzantine heartland. In my case, this meant a Crusade across Northern Africa against the the game’s great Muslim power: Egypt. So I did what empires so often do, which was to open another imperial frontier in an attempt to gain new resources that I could then turn against my main rival. In one of my campaigns as the English in Medieval: Total War, I was mired in a war of attrition against the seemingly endless strength of the Byzantine Empire, on a front stretching from Poland to Italy.