Aside from his foundation of Marischal College in 1593, later one of the two constituent colleges of the University of Aberdeen, and his reputed great wealth, there was nothing particularly special about George Keith, 5th Earl Marischal (1554–1623). But it is his very ordinariness, contends Miles Kerr-Peterson, that makes Marischal worthy of attention, for in reconstructing his activities, we can acquire valuable insights into the mainstream of early-modern Scotland's still patchily-understood aristocratic culture, and through it the functioning of society and the state more broadly. To test this hypothesis, Kerr-Peterson adopts a broadly thematic approach, assessing, in turn, Marischal's political, familial, religious and economic policies, before ending with a focused case study of his patronage of Marischal College itself. The result is stimulating, though perhaps rather inconsistently so. The analysis of political affairs is fascinating, particularly for the light it sheds on the interaction between aristocratic power and James vi's burgeoning household and bureaucracy. Meanwhile, the discussion of local lordship through the prisms of feuding, economic ‘improvement’ and cultural patronage is very helpful, and Kerr-Peterson's overall contention that Marischal was no less powerful or consequential a lord for being essentially a local rather than a national player is surely convincing. Conversely, the book's main problem lies in the fragmented nature of its source base, thanks principally to the loss of the Keith family's papers following their forfeiture for turning out in the 1715 Jacobite rising. That naturally limits how much Kerr-Peterson is able to say, and while he invariably handles the surviving evidence skilfully, the fundamental paucity of the documentation means that, for example, his discussion of religious patronage is frustratingly tentative and non-revelatory (which, incidentally, makes the prominence of ‘Protestant’ in the book's title a little strange). While, therefore, this is a somewhat uneven book – and one that still carries a strong echo of its beginnings as a PhD thesis, not least in its provision of some rather unnecessary genealogical appendices – its attentive, textured reconstruction of Marischal's career is nevertheless extremely valuable. In providing one of the most detailed portraits of an early-modern Scottish nobleman ever published, Kerr-Peterson has given us fresh insights into both the development of aristocratic culture and the nature of socio-political power during a period of dramatic evolution for both.