Newnham Priory was a priory in Newnham, Bedford, Bedfordshire, England.
The Augustinian priory of Newnham was not actually built until some time after the accession of Henry II, but it may fairly claim to be the most ancient religious foundation in Bedfordshire, in so far as it still held the church of St. Paul's and succeeded to the endowments of the secular canons there. It is implied in the Domesday Book that these latter were in Bedford before the Conquest; and Leland records the tradition that they lived in houses 'round about the Church.' How long they had been there, and whether they were in any way descended from the original monastery of Bedford, named in 971 in the Anglo-Saxon Chronicle, it is difficult now to discover: all we know is that they were living at the Conquest as secular canons, and had property at Biddenham and Bedford. Their patron at this time must have been Hugh de Beauchamp, who first held the barony of Bedford; a little later Payn de Beauchamp, son of Hugh, and his sister Ellen are both named as benefactors.
However the foundation of the priory of Newnham was the work of Simon de Beauchamp, son of Payn, about 1166. Tradition ascribes the change to the scandal caused by the affair of Philip de Broi, one of the canons, whose name has become famous in connection with the quarrel between Thomas Becket and Henry II. This man was accused of homicide, and cleared himself by oath; but the evidence was so much against him that Simon Fitz Peter, the king's justiciar, summoned him to a new trial. On receiving the summons, Philip broke out into such angry words and insults against the justiciar that the king considered his own authority slighted in the person of his delegate; and the archbishop, fearing that a very severe punishment would follow, interposed and passed sentence upon the offender in his own court. This sentence—the loss of his prebend, and further some penance for two years only—was considered by the king as a glaring instance of the failure of the ecclesiastical courts in dealing with serious crimes; it contributed something towards the estrangement between him and the archbishop, and also made it advisable for the canons to change their place of residence.