 Complete the following phrase:  Landulf was forced to make submission to the Byzantine Empire, whose Italian catepan Boiannes had built the fortified city of Troia nearby. In 1022, the Emperor Henry II joined his army with two other armies under Poppo of Aquileia and Pilgrim of Cologne at Benevento, which submitted after a quick siege. From there they marched on Troia, but failed to take it. After making submission to the Western Emperor, Landulf is not heard of again in the pages of history until his death. He was succeeded by his son Pandulf. His other son, Atenulf, as later elected leader of the 