In 1081, while the Byzantine Empire was mired in a succession crisis, Robert Guiscard, Norman Duke of Apulia-Calabria, sought to take advantage and launched his conquest. To maintain appearances, he ...

William the Conqueror sought papal endorsement for his invasion of England, and Robert Guiscard and other Normans who led the Norman invasion of Italy claimed their battles were driven by faith.

However, there are exceptions, such as Godfrey of Bouillon, Tancred of Galilee, and Robert Guiscard. The latter, grandfather of the former, was also the father of Bohemond of Taranto, his firstborn, ...