This volume is the fourteenth to be published in the British Academy Anglo-Saxon Charters series and the ninth to be edited by Susan Kelly. The series editor describes the project as representing ‘fundamental research’, a claim that is fully justified and particularly appropriate, since the monastery was founded twice, first as Medeshamstede in the late seventh century and then as Burh (later Peterborough) in about 970. The thirty-one pre-Conquest charters, edited here, provide almost all of the evidence for the two foundations. They have attracted critical comment from the beginning. At the papal court in 1146 the alleged privilege of Pope Agatho was rejected as ‘not drafted in the correct form’ (p. 165; no. 2). When a diploma of King Edgar was produced before the Quo Warranto commissioners in 1285 they concluded, no less rightly, though for the wrong reasons, that ‘no faith could be placed upon it’ (p. 264; no. 16). Kelly's edition demonstrates that their scepticism was fully justified. These were ‘part of an ambitious dossier of fabricated documents taking the minster's history from its seventh-century foundation to the reign of William the Conqueror’ (p. 165). The date of the forgeries was the first half of the twelfth century, when the monastery produced also a Latin chronicle, that of Hugh Candidus, and the final E Text of the Anglo-Saxon chronicle, into both of which the forged materials were assimilated. The purpose of the forgeries was to give the monastery, particularly the first foundation at Medeshamstede, a past, one compatible with its claims to be ‘the most important Petrine centre in England’ (p. 66). As such, so Hugh Candidus asserted, interpreting genuine documents, Medeshamstede had been the head of a federation of minster churches, including Breedon on the Hill and Brixworth and, further afield, Bermondsey and Woking. Sir Frank Stenton viewed his claim sympathetically, in an influential paper, ‘Medeshamstede and its colonies’, first published in 1933. Kelly, very courteously, demolishes it. There was no such federation; the archive is more likely that of Breedon than of Medeshamstede; and it came to Peterborough as a result of ‘the displacement and disruption of various monasteries in the Danelaw’ (p. 78) in the tenth century. Here, and throughout, Kelly presents some very technical material with clarity, common sense and a sustained critical intelligence. The volume provides an essential starting-point for discussion not just of the foundation of the house but for all aspects of its later history.