Northampton Castle

Northampton Castle was built under the stewardship of Simon de Senlis, the first Earl of Northampton, in 1084, on ground outside the western city gate. Deep trenches defended three sides, while a branch of the River Nene gave a natural barrier to the west. Work took several years to finish: the castle goes unmentioned in the Domesday Book, the great survey of England completed in 1086. What grew there became one of the most prominent Norman castles in England, with extensive grounds and a large keep, its gates ringed by earthen bulwarks used to mount artillery.

By the reign of Henry II the castle was in the hands of the Crown, and in 1164 Thomas Becket was tried there before a great council. He escaped by dressing as a monk and fled to France. In the First Barons' War between King John and his barons, the barons used the castle as a stronghold. In May 1215 rebels who had renounced their fealty to John besieged it without success. When the king prevailed, the castle was entrusted to Falkes de Breauté, whom John admired for his courage during the war.

In 1264, in the Second Barons' War between Henry III and his nobles, the castle was owned by the confederate barons and governed by Simon de Montfort. The king defeated the garrison at the Battle of Northampton that year and the castle reverted to the Crown. It stayed in royal hands until three years into Edward III's reign, when Thomas Wake, then sheriff of Blisworth, claimed it belonged to the county under his jurisdiction.

By 1452, thirty years into the reign of Henry VI, it had become a property to let: Robert Caldecote took it for twenty years at five pounds a year, the rent carrying with it the herbage within the walls and in the trenches, a certain meadow, and the right of fishing in the river.

During the English Civil War the castle was used by the Parliamentarians. In revenge for that, Charles II ordered in 1662 that the town walls and the castle's defences be slighted, damaged and made useless so they could not serve as a fortification again. What was left of it worked afterwards as a court and a gaol, its state of repair gradually worsening; by the late seventeenth century it was in the hands of Robert Haselrig.

The railways initially by-passed Northampton, the main line out of Euston running about five miles south of the town. A loop line through Northampton was built in 1879, and in that same year the London and North Western Railway demolished the castle and its foundations to make room for Northampton Castle railway station. Only some earth banks beside St Andrew's Road and the re-positioned postern gate, a minor archway, survived. The station was rebuilt in 1963–64 and the suffix "Castle" dropped, since it had become the only remaining station in the town.

Two rounds of digging have since recovered something of what the railway took. Excavation in 1961, ahead of that rebuilding, exposed twelfth-century defences: a ditch ninety feet wide and thirty feet deep, and a bank eighty feet wide and twenty feet high. More extensive work in 2012–13, before the station was enlarged again, turned up Anglo-Saxon material including a brooch, pottery fragments and an ironstone wall. The site is a scheduled monument; a volunteer group, the Friends of Northampton Castle, publicises its history, and in July 2025 heritage poles were set up in Castle Park to mark the line of the castle's perimeter.