Roger Borsa (1060/1061 – 22 February 1111) was the Norman Duke of Apulia and Calabria and effective ruler of southern Italy from 1085 until his death.
[1] His ambitious mother arranged for Roger to succeed his father in place of Robert Guiscard's eldest son by another wife, Bohemond of Taranto.
Roger also granted him the vassalage of Geoffrey of Conversano, thus giving Bohemond control over Brindisi,[3] as well as Cosenza and other holdings he desired allodially.
In September 1089 Roger Borsa was officially invested with the Duchy of Apulia by Pope Urban II at the Synod of Melfi.
In 1090, he and Urban tried unsuccessfully to convince Bruno of Cologne, founder of the Carthusian Order, to accept election to the archbishopric of Reggio di Calabria.
In October 1104, Roger besieged William, Count of Monte Sant'Angelo, who was at that time independent and pledged to the Byzantines, and expelled him from the Gargano, abolishing the county.