The black-bearded barbarian: The life of George Leslie Mackay of Formosa follows the journey of an individual who leaves the familiarity of home to pursue a mission driven by conviction and purpose. From a childhood shaped by determination and curiosity, the narrative moves toward the moment when this figure chooses a distant land as the place to carry out meaningful work. The book highlights how inner resolve can guide someone toward challenges far beyond anything imagined in youth. The story emphasizes courage in the face of unfamiliar customs, demanding environments, and resistance to new ideas. It also reflects how personal belief can push someone to embrace struggle, discomfort, and uncertainty. Through vivid scenes, the work shows how perseverance gradually changes both the person and the community encountered. More than a record of historical events, the book portrays how a life shaped by service can inspire transformation, revealing the deeper power of commitment and compassion even when the destination is unknown.