influential French architect who created mansions now regarded as the epitome of early Rococo residential design.

De Cotte was a pupil and assistant of the architect Jules Hardouin-Mansart and became his brother-in-law about 1683. After Mansart's death in 1708, de Cotte succeeded him as first architect to the king. Preceding this appointment, de Cotte had designed or decorated several city and country mansions, including the Hôtel des Mousquetaires Noirs (1699), and had worked closely with Mansart on additions to the Hôtel des Invalides. De Cotte's later designs for houses include those of the Hôtel de Lude (1710; now destroyed), the Hôtel d'Estrées (1713), and the Hôtel du Maine (1718; now destroyed). As his reputation grew, de Cotte was called upon to design important ecclesiastical residences, notably the episcopal palaces at Verdun (completed 1735) and the Palais de Rohan at Strasbourg (completed 1735). In these buildings he created varied interior spaces but preserved an elegantly symmetrical facade. These buildings are considered striking examples of the Rococo palace; they combine interior comfort with noble, simple, and elegant facades that have an impressive public grandeur.

De Cotte decorated the Chapel of Versailles (1708–10; according to Mansart's design) and the choir of Notre-Dame de Paris (1708–14), designed the acclaimed portal of the Church of Saint-Roch, Paris (1731–42), and reconstructed the Abbey of Saint-Denis (1700–35). In his later years he received many commissions from abroad, including palaces and castles at Brühl, Frankfurt am Main, and Bonn, and the royal hunting lodge in Turin, Italy.