 That he called himself a Duke is known from a charter at Stavelot 21 July 905, but this was during a period when Gebhard was Duke of Lotharingia.Reginar was originally a supporter of Zwentibold in 895, but he broke with the king in 898.He and some other magnates who had been key to Zwentibold's election three years earlier then took the opportunity provided by the death of Odo of West Francia to invite Charles the Simple to become king in Lotharingia.