In this thesis I investigate the relationship between ‘new’ philosophy and salvation in the scholarship of three seventeenth-century English Catholics: Sir Kenelm Digby (1603–1665), Thomas White (1593–1676), and Franciscus à Sancta Clara (c. 1598–1680). My first overarching argument is that salvation is an invaluable and historiographically underappreciated conceptual focus that improves our current appreciation of the seventeenth century’s philosophical advancements. By investigating how three significant but understudied scholars used their ‘new’ philosophies to aid their readers’ salvation, I demonstrate that theology continued to play a significant role in motivating early modern philosophical innovation—innovation that has previously been characterised as leading to theology’s marginalisation. This thesis also constitutes an unprecedentedly comparative and detailed contribution to the intellectual history of seventeenth-century English Catholicism. I make this contribution in two ways. First, I show that idiosyncratic intellectual contexts led Digby, White, and Sancta Clara to demonstrate ‘new’ philosophy’s importance to salvation in contrasting ways. Recovering these divergent approaches leads to a more sophisticated appreciation of English Catholic scholarly identity in the seventeenth century. Second, I show that Digby, White, and Sancta Clara asserted their confessional identity through a ‘turn towards the individual’ in their ecclesiologies. More specifically, I evidence that, through an emphasis on their reader’s ability to progress towards salvation via rational deliberation, they made criticisms of the institutional Church, which they saw as impeding the individual Catholic’s intellectual and spiritual self-improvement. In order to make these contributions, this thesis is structured as three chapters: chapter one examines the role salvation played in Digby’s early and mature philosophy; chapter two uncovers how White’s preoccupation with salvation influenced his numerous theological and philosophical works; and chapter three uses Sancta Clara’s writings on salvation to reassess his philosophy and scholarly motivations.