Castle Acre Priory is thought to have been founded in 1089 by William de Warenne the son the 1st Earl of Surrey who had founded England's first Cluniac priory at Lewes in 1077. The order originated from Burgundy. Originally the priory was sited within the walls of Castle Acre Castle, but this proved too small and inconvenient for the monks, hence the priory was relocated to the present site in the castle grounds about one year later.
The nave of the church is one of the oldest parts of the ruin, however subsequent additions continued to be added up until the priory was dissolved in 1537 under Henry VIII, and when the King gave the dissolved priory to the Duke of Norfolk complete with its estates, the remaining monks were turned out. The estates eventually passed to Sir Edward Coke, whose descendant, the Earl of Leicester now owns the ruins and Castle Acre Castle.
The ruins today are very impressive, the great west front of the building is almost complete, and the prior's lodging is in a similar condition. The priory is now in the care of English Heritage, along with the nearby Castle Acre Bailey Gate and Castle Acre Castle.