This groundbreaking Companion explores how Counter-Reformation sanctity reshaped religious identities, sacred traditions, and devotional practices that transformed Catholicism into the first global religion. Offering a fresh perspective on early modern Catholicism, it moves beyond traditional debates about Reformation and Reform and presents sanctity as the defining lens through which to view the period's transformative changes. By examining the lives, representations, and global impact of saints, the Companion demonstrates how sanctity countered the Protestant challenge and also transformed the very fabric of Catholicism between 1500 and 1750. Organized into four thematic sections – models of sanctity, the creation and contestation of sanctity, the representation of saints, and everyday interactions with saints – the volume also provides insight into the role of holiness during this pivotal period in Church history. Connecting history, theology, art history, and material culture, this interdisciplinary Companion serves as an indispensable resource for scholars and students seeking a comprehensive understanding of early modern Catholicism's influence on European and global history.