Robert, Count of Clermont

Robert, Count of Clermont was the sixth son of French King Louis IX and the younger brother of Philip III of France. In 1279, due to him suffering a head injury in his first jousting tournament, Robert became an invalid for the rest of his life. After Henry III of France was assassinated in 1589 and the House of Valois ran out of males (since females and female-line descendants of French royalty could not inherit the French throne), Henry IV of France became the first French King from the House of Bourbon due to his male-line ancestry from Robert, Count of Clermont.
Family and descendants.
Robert married Beatrice, Duchess of Bourbon and together they had a son, Louis I, Duke of Bourbon, who was the founder of the House of Bourbon through his two sons. The elder line of the House of Bourbon was made up of the Dukes of Bourbon, and it became extinct in the male line in 1527. Meanwhile, the younger line of the House of Bourbon, the House of Bourbon-La Marche–later known as the House of Bourbon-Vendome, acquired the French throne in 1589 once the House of Valois became extinct in the male line.