Chapter 4 focuses on the League’s resolution of conflicts involving members during its first twelve years. The League’s operation during this time reveals the challenges facing the Empire and its territories after the 1555 adoption of new peace-keeping regulations known as the Imperial Enforcement Ordinance. By offering a venue for the mediation of disputes that imperial organs of government could not or would not settle, the League of Landsberg served as a vehicle for implementing the Enforcement Ordinance in its member regions. In the process, the League’s operation simultaneously bolstered the Enforcement Ordinance’s regime while sapping jurisdiction away from imperial governmental bodies. Ultimately, the League created interdependencies between the imperial core and the Empire’s regions that set the stage for later debates over what alliances could and should do within the Empire’s structure.

Chapter 5 investigates the League of Landsberg’s failed attempt to admit new Protestant and Catholic territories in the early 1570s, including the Low Countries. The League’s proposed expansion presented an opportunity to create a lasting peace in the Empire by forging new ties among competing territories. At multiple points, however, both Catholics and Protestants rejected this possibility, as neither party wished to cede primary authority in the alliance. Even as the League continued to resolve neighborly disputes, support for its exercise of shared sovereignty eroded. Related processes operated in the Low Countries during the 1570s, where civil war spawned competing alliances: the Union of Arras and the Union of Utrecht. Including members that supported a variety of religious policies, the Union of Utrecht tried to solve the problem of religious diversity by devolving authority over religion to provincial governments. Such a solution meant that much of the United Provinces’ subsequent political development depended on how different provincial authorities interpreted the meaning of the Union’s treaty of alliance. This dynamic remained at the heart of the Dutch Republic and its exercise of shared sovereignty throughout the late sixteenth and seventeenth centuries.

Chapter 3 explores the aftermath of the Braunschweig-Wolfenbüttel invasion for both the Empire and the Low Countries. The 1540s and 1550s witnessed significant upheaval that encouraged multiple plans for corporate alliance, including an effort to restructure the Empire and the Low Countries into a massive Imperial League headed by Emperor Charles V. During this era, the politics of alliance became tied to a growing conviction among Catholic and Protestant Estates that the Empire’s well-being depended on the preservation of one’s own religious confession. These developments had major implications for the Low Countries, as Charles’s failure to create the Imperial League led to a redefinition of the relationship between the Habsburg Netherlands and the Empire in the 1548 Burgundian Transaction. Ultimately, the aftermath of the Schmalkaldic League’s military defeat, coupled with the shared desire of Protestants and Catholics to use alliances to preserve peace and their respective religious faiths, created the context for the 1555 Religious Peace of Augsburg. This agreement, in turn, set the parameters for corporate leagues for decades to come.