Großmeister Wilhelm Becker, head of the Order of St. Boniface, is sent to represent Köln, as the main branch of the royal family are busy at other weddings (and Johannes doesn't trust any of his siblings or their families). He brings a gift for Louis - a perfect steel sword, forged with steel from Köln by the finest smithies the Order of St. Boniface has. The pommel is inlaid with a large sapphire, representing the blue of Valois and Köln.
OOC: Köln is pretty much the producer of the best steel outside of Damascus (historically the area has always had lots of iron and steel) and the Order of St. Boniface, like any Christian Order, has incredibly good equipment, so this sword is
awesome