Frère Jacques/Brother John and Ah vous dirai-je Maman/Twinkle Twinkle Little Star crossed the border but you wouldn't call that an influence, would you?
Troubadours: the 1st one, Guilhèm IX de Peitieus/Guillaume IX de Poitiers, was duke of Aquitaine (West of Occitania), the most famous, Bernat de Ventadorn, was from Limousin (North-Northwest of Occitania). The movement spread eastwards, so reached Languedoc later.