In this public lecture Kevin Vallier will introduce and discuss 'Catholic integralism', drawing on the arguments of his 2023 Oxford University Press book 'All the Kingdoms of the World: On Radical Religious Alternatives to Liberalism'. Integralism is an increasingly popular account of the right relationship between the church and state within Catholic political thought, which holds that the state should recognise and uphold the true religion. In thus rejects many of the central tenets of contemporary liberalism.