The Delaval Family was of Norman descent and lived in Northumbria from the Norman Conquest onwards. At the commencement of the 18th century, there was only one male Delaval remaining, a sea captain. He inherited from his uncle, an Admiral, a great unfinished house designed by Sir John Vanbrugh. The fate of this sea captain's large family bore out the Delaval Family reputation for wildness and violent deaths. These papers illustrate another side of the family. Sir Francis Blake Delaval, the sea captain's eldest son was known as the greatest libertine of his age. Sir John Delaval, his brother (later John, Lord Delaval), was one of its most able business men. These papers are mostly Sir John Delaval's. At Seaton Delaval in Northumberland, was situated not only Sir John Vanbrugh's new house, but also a considerable industrial empire. There was Seaton Sluice, the Hartley Collieries, the Hartley Bottle Works, the Salt Pans and the Quarry. Lord Delaval was ruined by the Napoleonic Wars. He died a comparatively poor man. His brother Edward inherited Seaton Delaval, but left it empty. In 1822, it caught fire and became a shell. There were no male Delavals left to inherit and the house passed to the Astley family (through Rhoda Delaval's marriage to Sir Jacob Astley). It remains in the possession of the Astleys and they have restored it.