The castle originated as a tower built in 1571 by Pierre le Sire, a forge master who operated ironworks along the Biesme stream at the southern end of the village. This tower is the oldest surviving part of the structure. His son François de Sire, a captain of infantry, inherited the tower, forges, and surrounding lands. François was ennobled in 1610 by Archdukes
Albert and
Isabella. In 1665, Marguerite de Sire sold the property to Jean Desmanet, from a family of iron masters ennobled in 1660. Desmanet became the first lord of Sart-Eustache. His son Martin-Alexandre Desmanet succeeded him in 1701 and acquired the neighbouring Petit Sart fief in 1702 and the seigneury of Biesme in 1709. The forges ceased operation around 1720. In 1838, the castle and its lands passed to the de Bruges family, then in 1876 to Baron Guillaume de Giey. Through marriage, the property subsequently passed to the d'Orjo de Marchovelette family, who held it through the 20th century. ==Architecture==