John Constable, the revolutionary nineteenth-century painter of the landscapes and skies of southern England, is Britain's best-loved but perhaps least understood artist. His paintings reflect visions of landscape that shocked and perplexed his contemporaries: attentive to detail, spontaneous in gesture, brave in their use of colour. What we learn from his landscapes is that Constable had sharp local knowledge of Suffolk, a clarity of expression of the skyscapes above Hampstead, an understanding of the human tides in London and Brighton, and a rare ability in his late paintings of Salisbury Cathedral to transform silent suppressed passion into paint. Yet Constable was also an active and energetic correspondent. His letters and diaries - there are over one thousand letters from and to him - reveal a man of passion, opinion and discord, while his character and personality is concealed behind the high shimmering colour of his paintings. They reveal too the lives and circumstances of his brothers and his sisters, his cousins and his aunts, who serve to define the social and economic landscape against which he can be most clearly seen. These multifaceted reflections draw a sharp picture of the person, as well as the painter. James Hamilton's biography reveals a complex, troubled man, and explodes previous mythologies about this timeless artist, and establishes him in his proper context as a giant of European art.