Ashby-de-ka-Zouche takes its name from the Zouche family whose line died out in 1399. In 1464, Ashby was one of the estates granted to William, Lord Hastings, as a reward for his services to Edward IV. Hastings held the office of Lord Chamberlain and, in 1474, he obtained a license to crenellate his houses at Ashby and Kirby Muxloe.

During the Civil War, Henry Hastings strengthened the castle with earthen redoubts and turned it into the chief center of Royalist resistance in the county. The garrison endured over a year of siege before surrendering on honorable terms in February, 1646. The Hastings Tower was slighted by order of Parliament, but the rest of the castle remained habitable into the eighteenth century. It is now all ruined.

Before Lord Hastings, there was only a manor house here, though it was a fine one in keeping with the status of the Zouches. Hastings made the older buildings the core of his mansion. They form a range centered upon a late Norman hall, flanked by the solar and a buttery and pantry wing. In the fourteenth century, the massive kitchen was added to the complex. Lord Hastings modernized these buildings and extended the range with the addition of a fine chapel in the prevailing Perpendicular style.

Following the license to crenellate, he built a curtain around the manor house and raised the mighty square tower, which is named after him. The curtain cannot have been a very formidable obstacle - only a portion survives-but the Hastings Tower is still impressive. It is one of the best examples of a late medieval tower house, providing its owner with a dignified but secure residence. It stands detached from the manorial buildings, facing them across the courtyard. The tower is built in very fine ashlar masonry.