||Thirteenth-century England was a special place and time to be a bishop. Like their predecessors, these bishops were key members of the regnal community: anointers of kings, tenants-in-chief, pastors, counsellors, scholars, diplomats, the brothers and friends of kings and barons, and the protectors of the weak. But now circumstance and personality converged to produce an uncommonly dedicated episcopate-dedicated not only to its pastoral mission but also to the defence of the kingdom and the oversight of royal government. This cohort was bound by corporate solidarity and a vigorous culture, and possessed an authority to reform the king, and so influence political events, unknown by the episcopates of other kingdoms. These bishops were, then, to place themselves at the heart of the dramatic events of this era. This volume examines the interaction between the bishops' actions on the ground and their culture, identity, and political thought. In so doing it reveals how the Montfortian bishops were forced to construct a new philosophy of power in the crucible of political crisis, and thus presents a new ideal-type in the study of politics and political thought: spontaneous ideology.