This is by far the most substantial biography of Harrison to date, and it will endure as the standard account of its subject for many years to come. The book is massively researched, the author having read virtually all the secondary sources relevant to his topic, and mined all the pertinent manuscripts in national and local archives. Farr rightly emphasises Harrison's millenarian providentialist Fifth Monarchism as the mainspring of his military and political activism. It was his religion that gave him the courage to risk his life on the battlefield, and the boldness to demand that Charles Stuart, ‘that man of blood’, should be brought to trial for his supposed crimes against the godly. Farr vigorously contests the view of previous historians that Harrison had little aptitude for the hum-drum daily work of politics. He points to the many committees on which Harrison served, the number of times that he acted as a teller in parliamentary divisions, and his membership of the Council of State: ‘Harrison was no other-worldly millenarian, but was involved in practical politics' (p. 199). Yet Farr has to admit that his attendance at the Council of State was patchy, and that he was not able to exploit his committee memberships to obtain patronage for his friends. Nor was he a match for his chief political rival, Major-General John Lambert, who came out on top in his struggle for Cromwell's support for his proposed constitution for England in 1653. The book brings to light several fascinating details for the first time. In the 1650s, for example, Harrison bought land in Bedford, which he used to support fellow religious radicals, among them John Bunyan, author of The pilgrim's progress (p. 244). Farr also comments on the death of Harrison's first-born son, a mere two days after the execution of Charles i, of which he was one of the leading proponents: ‘Whatever Harrison's reaction to the death of his first son, part of it would have been a reflection on providence and in the context of the politics of regicide’ (p. 240). Harrison himself made an implicit connexion between the two events, when he admitted at his own trial in 1660 that ‘I have many times sought the Lord with Tears to know if I had done amiss in it’ (quoted at p. 32).