Why and how did English society embrace the prison as an answer to social problems? This study uncovers an important part of this story, revealing the growing centrality of prisons in early modern England to everyday social relations based on credit and debt. Between 1560 and 1700, prisons became essential to disciplining economic and moral life, provoking growing anxiety over incarceration and loss of liberty. In turn, new ideas crystallised about prisons as tools of coercion, deterrence, punishment and rehabilitation, while novel abolitionist politics developed among prison activists. This came to a head during the English Revolution, when prisoners' longstanding antagonism towards state and legal institutions entered radical milieus and law reform movements, impacting debates over authority, tyranny and liberty. This study reveals how straining credit networks, swelling prison populations and socioeconomic upheaval reshaped early modern society and politics. In doing so, Richard Thomas Bell sheds new light on the development of carceral ideas that remain fundamental, yet increasingly controversial, in contemporary society.