Background
He was a younger son of Lord William II of Béthune (d 1214) and his wife, Mathilda of Dendermonde.
He was a younger son of Lord William II of Béthune (d 1214) and his wife, Mathilda of Dendermonde.
He served as a knight and military leader in Flanders and England before inheriting his family territories in France and the Low Countries. He joined the Seventh Crusade, but died en route to the eastern Mediterranean. He therefore decided to become a knight at the court of Count Ferdinand of Flanders.
The House of Bethune was one of the more influential families in Artois, which had been a Flemish fief until Flanders had to cede it to the French heir apparent Louis, the son of Isabella of Hainault.
Count Baldwin IX of Flanders had ceded Artois to Hainault in the Treaty of Péronne. This brought him into conflict with the French royal family.
In 1213, Robert accompanied Count Ferdinand into exile in England after King Philip II of France had invaded Flanders. Later that year, he and the Earl of Salisbury led a successful attack on the French fleet in the port of Damme, thereby thwarting an impending invasion of England.
The following year, he participated in the decisive Battle of Bouvines (27 July 1214).
Robert was taken prisoner by a French knight, who released him, after Robert promised to pay a ransom. This story was recorded by an anonymous chronicler, who was employed by Robert and who wrote between 1220 and 1223 a chronicle about the French kings entitled Chroniques des rois de France et ducs de Normandie Daniel of Béthune died childless in 1226 and Robert inherited the family territories around Béthune, Richebourg, Warneton and Dendermonde, as well as the hereditary post of advocatus of Abbey of Saint Vaast near Arras. In 1227, Count Ferdinand was released from prison.
He paid homage to the French king and gave his hope of recapturing Artois.
Robert apparently came closer to the French crown in the following years. In 1236, he is named as a guarantor of the Treaty of Péronne, which must imply that he now recognized this treaty.
In 1248, Robert decided to join the crusade of King Louis IX of France to Egypt (the Seventh Crusade). During a stopover in Sardinia, en route to Cyprus, he fell ill and died.
He was buried in Arras.