Complex sentence: The Château d'Écouen, in Écouen, north of Paris, was built in 1538--50 for Anne de Montmorency, who was made "connétable" in 1538.
Split into simpler sentences: The Château d'Écouen is a historical building in Écouen, north of Paris, France. It was built in 1538--1550 for Anne de Montmorency, who was made "connétable" in 1538.