the candidate was found in form of frédéric casimir de la tour d'auvergne, son of emmanuel théodose de la tour d'auvergne and marie armande victoire de la trémouille. he was the heir to the sovereign duchy of bouillon which the la tour d'auvergne's had ruled for over a century. as heir, he was styled the "prince de turenne". charlotte married frédéric casimir by proxy on 25 august 1723 at neuss (modern day germany). the couple met for the first time at strassburg on 20 september and were married formally.