Knowing the ‘hereditary enemy’: Austrian-Habsburg intelligence on the Ottoman Empire in the late sixteenth century

ABSTRACT Throughout the sixteenth century, the Ottoman Empire presented the most formidable challenge to the House of Habsburg’s predominance in Europe. This imperial rivalry and the military conflict which it generated made it vital that the Holy Roman Emperor and his advisors were kept informed about their powerful adversary to receive advance warning of impending attacks. For this reason, intelligence formed an important aspect of the day-to-day activities of the Aulic War Council, created in 1556 to coordinate the military defence of the Habsburg–Ottoman border, as well as the Austrian-Habsburgs’ resident ambassadors in Istanbul. Sources surviving in the Viennese archives provide valuable insights into the collection and dissemination of relevant information, as well as the organisation built by the Habsburg diplomatic presence in the Ottoman capital. In particular, this article examines ambassadorial expenditure accounts which provide insights into the financial aspects of Austrian-Habsburg intelligence in the period 1580–1583 and demonstrates that the business of intelligence was pursued by the Habsburgs in a more professional and orderly manner than historians usually acknowledge. Indeed, it was woven into the very fabric of the Aulic War Council as well as the Austrian-Habsburg diplomatic presence in Istanbul.