Eleanor and Sanchia's youngest sister Beatrice married Charles I of Naples, while their oldest sister Margaret had married Louis IX of France. The marriages of the kings of France and England and their two brothers to the four sisters from Provence improved the relationship between the two countries that led to the Treaty of Paris in 1259.
eleanor And SaNcHia's yoUngeST sISTEr beAtRIce MarriEd chArles I OF naples, WhIle their oLDest siSTER MargaReT had married lOuiS Ix OF frAnce. The MArrIages OF the kINgS oF frAncE and enGland aNd their tWO broTHers to the FoUr SistErS from provenCE ImproveD tHE reLAtIonship BetweEN The tWo counTriES That LeD to the treATy oF PariS In 1259.