The question of whether someone is psychologically healthy or mentally ill, and the fundamental nature of mental health underlying that question has been debated in cultural, academic, and clinical settings for millennia. This book provides an overview of how people have conceptualized and understood mental illness through the ages. The book begins by looking at mental illness in humanity’s evolutionary past then moves through the major historical epochs: the mythological, the Classical, the Middle Ages, the Renaissance, the Enlightenment, and Modern, and the Post-modern. At each point, it focuses on major elements that emerged regarding how people judged sanity and insanity and places major emphasis on the growing fields of psychiatry and psychology as they emerged and developed. As the book moves into the Twenty-First century, Dr. Jenkins presents his Integrated Model of knowledge, a systemic, holistic model of the psyche that creates a conceptual foundation for understanding both psychological wellness and disorder and approaching assessment and diagnosis. This text provides a valuable exploration of mental health and illness across the ages and gives those already well-versed in the subject matter a fresh perspective on the past and new model of knowledge and assessment for the future.