Magnus is as technically impressive as Greenvoe. Brown himself judged that his second novel was superior to his first, although he came to acknowledge that this view was not shared by most critics. His vision of events and values in twelfth-century Orkney is compelling, but his main achievement was setting these in contexts which resonate with modern readers: '... it occurred to me that the whole story would strike a modern reader as remote and unconnected with our situation in the twentieth century ... The life and death of Magnus must therefore be shown to be contemporary, and to have a resonance in the twentieth century.'

While unity of inspiration is provided by the focus on Magnus - the man of peace embroiled in civil war - Brown's variety of narrative method demonstrates the relevance of the Magnus-Hakon story to convulsions in societies remote from them in time and place. Far from being a compilation of previous pieces, as Brown's prefatory note suggested, the novel is a coherent indictment of political ambition and 'necessity'.

The book begins and ends with the common people, whose faith in their sense of community receives many shocks. Their suffering, resilience and dependence on personal relationships become a kind of comment on events. Their aristocratic cousins, on the other hand, regularly split the island's loyalties, and their constant interruptions of the agricultural rhythm by which the peasants and tinkers live, lower the people's morale. Brown's account of the earls' supporters ruining the crofters' patiently cultivated fields and, hence, destroying their attempts to sink roots and build a community, is a striking illustration of the need for someone to take Orkney in hand. In this, Magnus develops the themes of Greenvoe, but there is no prospect of a peaceful end to the competition between two Orkney earls.

One of the most dramatic moments in Brown's fiction occurs in Chapter Seven, 'The Killing', where an abrupt, unannounced time-shift creates a striking modernisation of the killing of Magnus, updated to the context of a Nazi concentration camp, a connection that was quite deliberate: 'The truth must be that such incidents are not isolated casual happenings in time, but are repetitions of some archetypal pattern.' The narrative voice also changes, passing to Lifolf, the cook, an unsophisticated man who distances himself from the atrocities of war going on around him, but who is forced to execute Magnus.