In many respects, there are contrasting and competing views at play when we look at Byzantium's relations with its neighbours – whether in the Black Sea region or elsewhere for that matter. On the one hand, it is possible to compile a picture of Byzantine interest in its neighbours, of the Byzantines gathering information about those on its periphery, of sensitivity and alertness to shifts in power beyond the Empire's frontiers, and of a state able and actively seeking to respond to such changes as necessary.             This contrasts sharply with the other – and in many ways the more dominant – picture which can be drawn from the historiography of the middle Byzantine period, with its relentless accent on Romanitas and on the superiority of Byzantium and its culture over those around it – to the point, indeed, where chroniclers fail even to record very substantial changes to the Empire's frontiers. So, for example, while we are certainly not lacking source material for the third quarter of the 11^th Century – with narrative accounts of Michael Psellos, Michael Attaleiates, John Skylitzes, Nikephoros Bryennios covering this period in considerable detail – it is striking to note that none of these historians discusses the growth of Norman power in southern Italy or the consequent collapse of Byzantine authority there; indeed, only one of these authors even mentions the fall of Bari in 1071 which brought to an end centuries of Byzantine power in Italy.