In 1155 Byzantine Emperor Manuel I allied with Pope Adrian IV and sent an expedition under Michael Palaiologos and John Doukas against the Normans of Sicily. OTL, the invasion was initially successful but stalled after Michael alienated their Italian allies. After Palaiologos was killed and Doukas captured, Manuel sent Alexios Axouch but the Byzantines were finally defeated at the Battle of Brindisi.
What if Manuel's expedition had succeeded? If he had sent Alexios Axouch earlier, along with or instead of Michael Palaiologos. Or if Michael Palaiologos didn't have such an attitude. Or what if he himself went to Souther Italy.
1. If his negotiations with the Popes still went sour, would he still support the Lombard League against Fredrerick Barbarossa? I guess he would have to.
2. How much was Manuel planning to annex? The Papal States and all of Southern Italy (or at least Bari) were eager for a restored Byzantine presence in Italy and the city of Ancona acted as a base during the expedition.
Would Manuel have tried to annex the entire Norman kingdom, including Sicily and Malta, or just restore the traditional Catepanate of Italy (Apulia/Longobardia, Lukania and Calabria) and leave two rump kingdoms in Sicily and Naples?
3. Would his later campaigns against the Hungarians, Seljuks, Danishmendids and Fatimids still take place? Would he have given any support to a Miaphysite uprising in Egypt like Michael VIII did during the War of the Sicilian Vespers?
What happens to Bela III?