The region known as Burgundy has had some of the most elastic borders of any region of France, and some of the various regions called 'Burgundy' at different times barely overlap at all. Imperial Burgundy included both the region around Besançon and Geneva, the heart of the Burgundian kingdom of four centuries earlier, and the region from Lyons and Vienne south to Arles and the Mediterranean. This latter, more southerly part of imperial Burgundy was sometimes called lower or cisjurane Burgundy and sometimes called Provence. This chapter focusses on the history of both halves of imperial Burgundy, including upper Burgundy and Provence, as well as that of the region which later became the French duchy of Burgundy, between the late ninth century and the early eleventh century. Radulf, the king of France who confirmed Charles-Constantine as count of Vienne after the death of Louis the Blind, was also a Bosonid, son of Duke Richard le Justicier of French Burgundy.