Chesterton presents an illuminating account of St. Francis of Assisi, bridging medieval mysticism and modern skepticism. Rejecting sentimental portraits, he portrays the Umbrian saint not merely as a lover of nature, but as a passionate troubadour of God whose asceticism, renunciation, and ecstatic humility rekindled European culture. From his dramatic youth to the stigmata on Mount Alverno, this biography reveals the radiant paradox of holy joy.