In the 17th century the property was acquired by Sir William Howard (father of the 1st
Earl of Carlisle) and was remodelled and substantially enlarged. The house was repurchased from the Earl of Carlisle in 1711 by Matthew Featherstonehaugh (1662–1762). A survey of 1715 disclosed 'an ancient and well-built structure'. The family remained in occupation until
Sir Matthew Fetherstonhaugh sold the property to
James Wallace about 1789. His son
Thomas Wallace carried out further alterations between 1812 and 1830. Lord Wallace bequeathed the estate to his nephew Colonel
James Hope (1807–1854), (son of the
Earl of Hopetoun), who changed his name to Hope-Wallace. The various alterations to the structure have resulted in a large
castellated and complex
country house, rectangular in form with a central courtyard and towers at each angle. In 1825, farmers working on the lands at Wydon Eals near Featherstone Castle discovered what was thought at first to be a buried oak tree trunk. However, when they proceeded to cut it with an axe, it was revealed to be an oaken coffin containing human remains. These bones steadily turned into dust when they were exposed to the atmosphere. The remains of four other wooden coffins were discovered in the same area. These
log-coffins have been stated to belong to the early medieval period, and similar examples have been found in the north and east of England. During
World War II, bordering the South Tyne river and stretching across a mile of Featherstone Park, there was
Camp 18, a
POW camp that housed 7000 German Officers after 1945. Some of the remains of the camp are still visible on the grounds of Featherstone Castle. The camp closed its doors on 15 May 1948. The remaining German officers were sent by bus to
Haltwhistle, from where they took the train to other clearing camps in Britain, and then they went to Germany. In 1950 the contents of the camp were sold. A memorial plaque was erected at the former entrance to the camp in 1982. ==Modern usage==