When browsing in a shop or library, my grandfather would always turn to the last few pages of a book. If he liked the end, then it was worth a read. Anyone doing this with The Thirty Years War would find the chapter on how the War was seen by those who experienced it first hand.The War began amidst the early modern “communications revolution” which witnessed the development of the first successful commercial print media. The War accelerated this, as the general uncertainty left all hungry for news. It also coincided with changing perceptions, as the spread of printed almanacs and calendars encouraged a more chronological sense of time. Ever more people recorded their lives in autobiographies, diaries, letters and family chronicles, many of which survive, offering an insight in how ordinary folk experienced extraordinary events.I include in the book Peter Hagendorf, author of the only surviving diary of a common soldier, who records the War as a travelogue as he tramped 22,400 kilometers to and fro across the Empire between 1625 and 1649. His laconic account of his own part in plundering Magdeburg (in his own home region!) contrasts with several more graphic accounts of other civil and military eyewitnesses, yet is typical of much contemporary testimony.Most contemporaries recount personal hardship, though this was clearly relative. Some record direct experience of violence. Others are silent, often probably suppressing trauma which fragmentary post-war evidence suggests resurfaced later in nightmares and psychological disorders. Fear is the most common emotion. The War represented a violent and unwelcome intrusion into communal and family life. Occasionally, some express relief when things turned out better than expected, such as a Catholic nun who recorded that though the Protestant Swedes “had appeared terrible towards us, as soon as they saw us and talked to us, they became patient and tender little lambs.” More usually, accounts break off, often in mid-sentence, their authors either unwilling to continue or no longer alive.I hope that my book makes such experience intelligible and relevant for readers today.The early seventeenth century seems very distant. Much of it is irretrievably lost and we shall never be able to reconstruct it “as it actually happened,” as Leopold von Ranke and other empirical historians once thought possible about the past. However, the seventeenth century was a formative period in Europe’s development and it has been woven into many of the basic assumptions used to understand today’s world. These include an international order based on sovereign states, allegedly ushered in by the Peace of Westphalia which concluded the War in 1648.The Peace of Westphalia is also associated with a shift to a more secular, tolerant society. I indicate in the book that this view is not entirely correct. The peace still left the Empire “holy” in the sense of Christian—all other faiths were denied recognition. Peace rested on defusing disputes by shifting them from contests over singular, absolute truth, and channeling them into arguments over particular rights which could be resolved through legal arbitration.This suggests that religion should not be written out altogether. It shaped how the War was perceived both then, and subsequently. The most vocal commentators were clergy who were more willing to see God’s hand at work, for example hailing the invading Swedish king, Gustavus Adolphus, as a “Lion of the North” sent to liberate not to conquer.More significantly, faith convinced several key players that they were justified in gambling their subjects’ lives to pursue their own risky agendas. And here, the experience of the seventeenth century offers a warning for our own times.