Blois was an important royal houses between the 15th and the 18th century. The site was occupied since the Roman time. Count Thibaud I, nicknamed the Cheater (a mean guy, who deserved his name!) put up a stone keep just before the year one thousand.
Blois county was bought in 1391 by Louis, duke of Orléans and king Charles VI's brother. At that time, the castle was described by famous chronicler Froissart as "huge, lush, the most beautiful of the Crown."
But Louis XII and Anne of Brittany arrived and the castle was completely transformed into a royal residence. Their blazons, a porcupine and an ermine, now decorated fronts. They raised the Logis Neuf ("New building"), finished in 1501.
They re-built the chapel of Saint-Calais, dedicated in 1508. They also laid out the gardens, completed by the Italian artist Pacello da Mercogliano: Queen's garden, King's garden which was a vegetable plot (with a keep 30 metres deep), an orangery, 2 tennis courts...
In the reign of François I, Renaissance style spread in France: Loges front with its Italian look dates back to this time. Henri IV, Louis XIII and Anne of Austria often sojourned in the castle. Then, Louis XIII gave Blois county to his brother Gaston of Orléans when he married Mrs. de Montpensier. They occupied the castle since 1634; they raised the Classical style wing: building works were completed by François Mansart.
But Gaston lose interested in his castle, and when the future king Louis XIV was born, the building site stopped. Poor castle! Very damaged, Blois needed a huge restoration. The architect Félix Duban did it between 1845 and 1870. He completely transformed inner apartments' layout!