Robert II shared the kingship with his father Hugh Capet after his coronation in 987 and became sole ruler in 996. Associating an heir with the throne helped establish continuity for the new Capetian dynasty. Royal power depended on the king's own lands, the support of bishops and abbots, and negotiation with great territorial lords, whose authority could exceed his within their regions.

After the death of his uncle Henry, Robert fought a prolonged contest for the Duchy of Burgundy and eventually brought it under his control. He also extended influence around Sens. Marriage formed another instrument of dynastic politics, but his union with Bertha of Burgundy provoked ecclesiastical condemnation because of their kinship. He subsequently married Constance of Arles, whose children became central to the succession and to conflict within the royal household.

Robert supported churches and monasteries during the revival associated with Cluniac reform. His image as the Pious was strengthened by religious writers, especially the monk Helgaud, whose favourable account needs to be read as a shaped portrayal of kingship. Religious patronage coexisted with coercion: in 1022 people condemned for heresy at Orleans were burned under royal authority. Disputes involving Constance and their sons troubled his later reign. He died in 1031 and was succeeded by Henry I. His government consolidated the dynasty while leaving substantial power in the hands of regional rulers.