Dattus or Datto was a Lombard leader from Bari, the brother-in-law of Melus of Bari. He joined his brother-in-law in a 1009 revolt against Byzantine authority in southern Italy. In 1010, the rebels took Ascoli and Troina. In March 1011, the catepan Basil Mesardonites and Leo Tornikios Kontoleon, the strategos of Cephalonia, disembarked with reinforcements from Constantinople. Basil immediately besieged the rebels in Bari. The Greek citizens of the city negotiated with Basil and forced the Lombar… (More on Dattus)