The long-standing acceptance of Habsburg as synonymous with Austria, even after the end of the Austro-Hungarian Empire, made any opposition to a Habsburg ruler or government inherently treacherous. Yet, Peter Thaler shows us, when Protestantism, predominately Lutheranism, took root amongst the nobility, towns and peasants of Austria, the Protestant cause became a vehicle for the articulation of an alternative, but not novel, legitimate political vision. For the dynasty, Austria was ‘the Catholic, absolutist Habsburg Empire … a political entity rooted in a princely family’; Protestant nobles, by contrast, ‘anchored their patriotism in the individual territories and their customary laws and privileges’ (p. 253). Thaler narrates how in the early decades of the Reformation, Protestantism found audiences amongst miners, merchants, burghers and students and also the landed nobility. With their right to practise their faith under threat from the ruler, these groupings naturally looked to the legitimate authority of the estates to provide the necessary legal defence. As a result, in each individual territory, the estates repeatedly required religious concessions in the expected negotiations when each new ruler took power. The rulers could not ignore the long-standing legal reality of ‘historical tradition and affirmed privileges’ (p. 125) and responded with political expediency, above all in undermining the cohesion of the estates – paring off towns, preventing the lower nobility from hosting religious worship, holding out the opportunity of service to the monarchy, insisting on Catholic leadership within the noble curia. Nimbly, Thaler takes the reader through the twists and turns of the timing, nature and progress of this competition across more than a century within the various territorial entities that made up Austria. Neither side sought the elimination of the other, he notes. The rulers’ goal was to neutralise the estates. The Calvinist Georg Tschernembl, the ‘thinker’ of the Protestant party, argued that the greater the privileges of a territory and its estates, the greater the reputation of its ruler, and even the most serious rebellion, by peasants in Upper Austria in the 1620s, was not principally anti-Habsburg. Yet loyalty to the hereditary ruler was not unconditional. While we need to continue to move beyond the political in exploring the confessional experience in early modern Austria – this study notes, for example, the significance of conscience, schooling, family rifts (not just amongst the Habsburgs) and mobility – with this stimulating study, Thaler has given us good reason to wonder what exactly we are saying when we talk of ‘Habsburg Austria’.