At the moment I've got my hands full with Ivar Ulfsson trying not to be captured by King William and his brother Odo, who are involved in a 'grudge match' with him in England (1066-71). Then I shall progress to Miklagard (Constantinople) by way of Roskilde (Dk) and Holmgard (Novgorod), so I shall start reading up about the political history of Byzantium in the later 11th Century. I have a book by George Ostrogorsky called a 'History of the Byzantine State'. Ivar and his friends will get there about the time Emperor John is beaten at Mantzikert in Asia Minor
Watch this space.