If there has been one constant throughout the history of human life, it’s disease. Disease-causing pathogens have always been present in our world and will undoubtedly continue to exist for the foreseeable future. This book examines the history of major plagues and pandemics from the 5th century CE to the present-day COVID-19 crisis. Each chapter tackles an individual pandemic and examines its causes, scope, and impact. Denial, prejudice, and scapegoating are societal patterns that consistently recur in response to the threat of disease. However, necessity breeds innovation, and past pandemics have spurred us to develop new technology, medical advancements, improved public health policies, and more practical infrastructure. Misinformation, however, is the enemy of progress, and learning how our predecessors responded when confronted with similar events helps us both understand and better prepare for present and future crises. COVID-19 will not be the last pandemic that humanity will experience. History demonstrates that we have overcome outbreaks of disease time and time again, and we will continue to do so using the lessons we have learned from our past. There will always be infectious diseases present in our world, but the casualties and scale of future pandemics will depend entirely on how well we can learn from our previous mistakes.