The new royal chapel was the final and crowning addition to the palace during the reign of Louis XIV. Work began in 1689 but was delayed and hampered by wars and not completed until 1710. The lead architect, Jules Hardouin-Mansart (1646–1708), was succeeded by his brother-in-law Robert de Cotte (1656–1735), under whose supervision more than 100 sculptors and painters decorated the interior and exterior. The slender, two-tiered design was inspired by the medieval Sainte-Chapelle in Paris, while the classical colonnade inside evokes the celebrated eastern façade of the Louvre.