In January 1212 Joan and Ferdinand tied the knot in Paris. Thereupon the young pair wished to go to the county of Flanders in order to take over the reins of power from Joan's uncle (her father's brother)
Philip,
margrave of Namur, and temporary regent for the county. During their journey to their new county the couple was taken captive by prince
Louis of France, who also took the cities of
Saint-Omer and
Aire-sur-la-Lys. Philip II let them know that he would release them once they signed a treaty in which they would cede the two captured towns to France. Eventually, on 25 February 1212, they both signed this treaty at
Pont-à-Vendin, a Flemish-Artesian border town on the
Deûle between
Lens and
Lille. Philip now thought that with Ferdinand he had appointed a count of Flanders who he could easily manipulate. ==References==