The chapel stands in the far extremity of the East Wing. It was built along with the wing, between 1498 and 1511, by Charles the Second de Chaumont-Amboise. This was during the reign of King Louis the Twelfth.
It has a small transept and a three-sided apse, facing north. Three large crown windows let light into the apse, and two smaller ones open up onto a section cut into latticework. Beneath these, are arches containing a 16th century frieze, similar to those in the Saint Hubert chapel at the Château d’Amboise. On either side of the nave, the twisted columns are decorated with arabesques crowned with shells.
Mass back in the de Broglies’ day
Gabriel-Louis Pringué, a writer and close friend of the Broglies, was a regular guest at Chaumont. In his book Trente ans de dîners en ville (30 years of dinners in town), he wrote: "Every Sunday, around a quarter past noon, the Princess de Broglie would telephone from her bed to say that at half past the hour, the chaplain could step up to the altar. We were to hear mass in the chapel, while she would be alone in the tribune of the Catherine de Medici room. At half past noon, the priest began mass, occasionally looking up to the tribune which remained empty. Having reached the Gospel and the tribune continuing to be empty, the priest began slowly saying prayers. It would sometimes go on for half an hour. Then suddenly, we would hear high-heels clacking on the stone floors of the historical apartments. A footman would lift a tapestry and the princess, her hair not yet done, in her nightdress and dressing gown, a sable round her neck, would appear and the servant would take her favourite Pekinese dog in exchange for her book of hours. She would put on her pince-nez and cough to announce her presence. The priest, awoken from his prayers, would jump, blinking up at the royal tribune. Then Mass continued. One day, the Count of Obidos, a Portuguese lord familiar with Chaumont told her: Princess, only you would dare to keep God waiting."
The stained-glass windows
The chapel's stained-glass windows are the product of three artists. First, the de Broglies' architect, Paul-Ernest Sanson, researched the château's origins and history which he resumed in a written text entitled Les seigneurs de Chaumont-sur-Loire, notices historiques (The Lords of Chaumont-sur-Loire: historical notes). Second, master glassmaker Georges Bardon was asked, in March 1884, to compose and make the windows following the architect's notes. Third, historical painter Jean-Paul Laurens was asked by Georges Bardon, with the agreement of the princely couple and their architect, to reproduce the sketches. The cooperation of three different branches ended with the installation of the five windows in July 1888.
All the stained-glass windows depict episodes in the life of the Chaumont-Amboise family:
> the central window is an episode from the Day of Judgment which features various figures from the history of Chaumont, such as Cardinal Georges d’Amboise, wearing red.
> the small window to the right again represents Cardinal Georges d’Amboise, brother of Charles the First and uncle of Charles the Second. Behind him, are his patron saint, Saint George, and below, is the cardinal's coat of arms.
> the small window to the left is a tribute to Louis the Twelfth. Behind him, is his patron saint, Saint Louis, and below, is the king's coat of arms.