Peace was finally concluded in Edirne in 1568, and renewed in 1576, 1584, and 1591. War would not again break out between the Habsburgs and Ottomans until 1593, in the Long Turkish War. However, throughout this period of peace small-scale warfare continued, a conflict known as the "Little War" . No large armies or sustained campaigns were launched, but authorities on both sides continually struggled with hostile raiders and forays across the poorly-demarcated border. Both sides, however, desired that peace continue.
Question: How many year time span was there between the first time peace was renewed and the last time peace was renewed?
Answer: 15