The Sainte-Chapelle church was erected in 1230 during the reign of King Louis the Saint. It predates the Sainte-Chapelle church in Paris by 10 years and was probably designed by the same architect, Pierre de Montreuil, although it lacks its counterpart's stained-glass windows. Etched on the keystones are illustrations believed to depict the King, his mother Blanche de Castille and Marguerite de Provence. These would then be the most ancient surviving portraits of members of the royal family.