IGNIS: London Catholicism is a book on the history of Catholicism in London, tracing its evolution from the early stages through the medieval period, the Reformation, and into contemporary Catholic life and faith. IGNIS, meaning "fire" in Latin, symbolises the spirited and undying nature of Catholicism in London. The book offers an in-depth exploration of how the faith has withstood trials and continues to flourish, like an unquenchable flame at the heart of the city. Through historical narratives and contemporary insights, IGNIS: London Catholicism illuminates the profound and lasting impact of Catholicism on London's spiritual and cultural landscape. This book delves into how the durable Catholic spirit has continually influenced London, highlighting the city's rich and complex religious history. From the initial establishment of Christian communities to the turbulent times of the Reformation, and through to the vibrant Catholic community of today, IGNIS: London Catholicism provides an in-depth exploration of how the faith has withstood trials and continues to flourish in the heart of London.