The Impact of the Austro-Turkish War (1663–1664) on the Consolidation of the Estates of the Holy Roman Empire and the Revival of the Imperial Defense System

This article assesses the impact of the Austro-Turkish War of 1663–1664 on the state of the Holy Roman Empire's defense institutions and the consolidation of its estates in the face of external threats. The study focuses on the transformation of the relationship between Emperor Leopold I and the imperial estates during the war. The study analyzes the negotiations between the imperial estates and the emperor at the Reichstag regarding military assistance against the Ottoman Empire. The author examines in detail such aspects of the topic as the strengthening of Leopold I's position as Holy Roman Emperor, the creation of a unified imperial army, and the approval of a temporary version of the imperial matricula. Particular attention is given to the legal nuances of the functioning of the imperial defense system in the second half of the 17th century. The research methodology involves working with the legal documents of the Reichstag. This corpus of documentation includes the following types of sources: the emperor's addresses to the Reichstag (Kaiserliche Proposition), the texts of imperial decrees (Reichsschlüsse), and decrees of the Imperial Commission (Kaiserliches Kommissionsdekret). Additional sources include the writings of 17th-century political journalists. The main conclusion of the study is the thesis that the outbreak of war with the Ottoman Empire in 1663 marked a qualitatively new stage in the existence of the Holy Roman Empire. An analysis of the sources shows that Emperor Leopold I succeeded in exploiting the religious underpinnings of the conflict and, acting as a defender of Christendom, united the imperial estates around himself, convincing them to send money and soldiers to fight the Turks. During the war, the imperial estates rallied around the figure of the emperor, an imperial army was created, and a temporary revision of the matricula was agreed upon. This allowed the Ottoman Empire to be militarily defeated and forced to sign a peace treaty. The study's novelty lies in its demonstration of the effectiveness of imperial institutions, which not only were not destroyed after the Peace of Westphalia but also continued to function successfully, ensuring the security of the imperial estates. Thus, the author makes a significant contribution to the historiographical debate about the viability of the Holy Roman Empire and its state structure after the end of the Thirty Years' War.