House of Courtenay

House of Courtenay is the name of two distinct noble families, both of which descended from Athon. Athon, the first lord of Courtenay (Seigneur de Courtenay), was himself apparently a descendant of the Counts of Sens and from Pharamond, reputed founder of the French monarchy in 420. Athon took advantage of the succession crisis in the Duchy of Burgundy between Otto-William, Duke of Burgundy and Robert II of France to capture a piece of land for himself, where he established his own seigneury (lordship), taking his surname from the town he founded and fortified.

In the 12th century, Renaud de Courtenay (d.1190), son of Milo de Courtenay (d.1127), moved to England after quarreling with King Louis VII:

The House of Bourbon, which acquired the French throne with Henry IV of France, was another cadet branch of the Capetian dynasty. Under the Salic law, males descended in male line from Hugh Capet are princes of the blood—i.e., they have the right to succeed to the French throne in the event that the male line of the royal family and of more senior princes die out. Hence, the then impoverished Capetian House of Courtenay, being agnatic descendants of Louis VI of France, sought to be acknowledged as "princes du sang" (Princes of the Blood Royal) and "cousins to the king," two titles normally reserved for the members of the royal family and prized for the seats at the Royal Council and the Parliament of Paris that they conferred upon its holders. Three Bourbon kings in a row - Henri IV, Louis XIII, and Louis XIV - turned down their petitions. That the Bourbon monarchs confined the French royalty to the descendants of Louis IX is evidenced by the Treaty of Montmartre (1662) which named the non-Capetian House of Lorraine as the next in line to the French throne after the Bourbons, thus bypassing the Courtenay branch, a Capetian family. Although the Courtenays protested against this clause, their claims to the princely title were never acknowledged by the Paris Court of Accounts. The last male member of the French Courtenays died in 1733, but his niece married the Marquis de Bauffremont, and her descendants assumed the title of "Prince de Courtenay" with dubious validity, which they bear to this day.

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