Robert IV the Strong (also known as Rutpert) (820-July 2, 866), was Margrave in Neustria. His family is named after him and called Robertians. He was first nominated by Charles the Bald missus dominicus in 853. Robert was the father of the kings Odo and Robert I of France. Robert was the great-grandfather of Hugh Capet and thus the ancestor of all the Capetians. His father was Robert of Worms.
While very little is known about the beginnings of the Robertian family, historians have been able to adduce that the family of nobles had its origins in Hesbaye or perhaps from the family of Chrodegang of Metz. During the reign of Louis the German, the Robertian family moved from East Francia to West Francia. After his arrival in West Francia, Charles the Bald showed his favour of the family defecting from his enemy Louis by assigning Robert to the lay abbacy of Marmoutier in 852. In 853 the position of missus dominicus in the provinces of Maine, Anjou, and Touraine was given him and he had de facto control of the ancient ducatus Cenomannicus, a vast duchy centred on Le Mans and corresponding to the regnum Neustriae. Robert's rise came at the expense of the established family of the Rorigonids and was designed to curb their regional power and to defend Neustria from Viking and Breton raids.
Despite the fact that he was a favoured noble of Charles, Robert joined a rebellion against the king in 858. He led the Frankish nobles of Neustria with the Bretons under Salomon in inviting Louis the German to invade West Francia and receive their homage. The revolt had been sparked by the marriage alliance between Charles and Erispoe, Duke of Brittany, and by the investment of Louis the Stammerer with the regnum Neustriae (856). These actions significantly curtailed the influence both of Salomon and Robert. Charles compensated Robert for the losses suffered in this civil war by giving him the counties of Autun and Nevers in Burgundy, which greatly enlarged his landholdings. In 856 he had to defend Autun from Louis the German following the death of Lothair I. But following Erispoe's assassination in November 857, both he and Salomon rebelled.
Louis the German reached OrlĂ©ans in September 858 and received delegations from the Breton and Neustrian leaders, as well as from Pepin II. The Neustrian rebels had chased Louis the Stammerer from Le Mans, his capital, earlier that year. In 861, Charles made peace with Robert and appointed him Count of Anjou, even though he had been involved in the revolt.
While count of Anjou, Robert was able to successfully defend the northern coast against the threat of a Viking invasion. In 862 Charles granted Louis the Stammerer, his son, the lay abbacy of Saint Martin of Tours, a small benefice in comparison with the kingdom he had received in 856 (and lost in 858). The young Louis rebelled and was quickly joined by Salomon, who supplied him with troops for a war against Robert.
In 862 two groups of Vikingsâ€”one the larger of two fleets recently forced out of the Seine by Charles the Bald, the other a fleet returning from a Mediterranean expeditionâ€”converged on Brittany, where one (the Mediterranean) was hired by the Breton duke Salomon to ravage the Loire valley. Robert captured twelve of their ships, killing all on board save a few who fled. He then opened negotiations with the former Seine Vikings, and hired them against Salomon for 6,000 pounds of silver. The purpose of this was doubtless to prevent them from entering the service of Salomon. Probably Robert had to collect a large amount in taxes to finance what was effectively a non-tributary Danegeld designed to keep the Vikings out of Neustria. The treaty between the Franks and the Vikings did not last more than a year: in 863 Salomon made peace and the Vikings, deprived of an enemy, ravaged Neustria.
Robert made war on Pepin II in his later years. In 863 he had to defend Autun again from Louis the German, this time after the death of Charles of Provence. Robert was in Neustria during 865 and 866, with Bretons and Vikings ravaging the environs of Le Mans.
In 866, Robert was killed at the Battle of Brissarthe while, unsurprisingly, defending Francia against a joint Breton-Viking raiding party, led by Salomon, Duke of Brittany, and the Viking chieftain Hastein. During the battle, Robert had entrapped the Viking commander in a nearby church. Thinking he was not endangered, Robert took off his armour and began to besiege the church. Once Robert was unarmoured, the trapped Vikings launched a surprise attack and killed him before he had time to re-arm. His success against the Vikings led to his heroic characterisation as "a second Maccabaeus" in the Annales Fuldenses.
The name of Robert's wife is not attested in primary sources. According to some modern scholars she was Adelaide or Adalais, a daughter of Hugh of Tours (and thus an Etichonid) and the widow of Conrad I of Auxerre (died 862), a Welf. Since Robert already had children by 862, Adelaide would have to have been his second wife. French genealogist Christian Settipani has identified the source of this identification as the unreliable twelfth-century Chronicle of Saint-BĂ©nigne de Dijon, which was interpolated into the chronicle of Alberic of Trois-Fontaines. The EuropĂ¤ische Stammtafeln has identified Robert's first wife as a certain Agane. Whatever the facts, two of Robert's sons became kings of France: Odo and Robert.