Henry David Thoreau was an American author, poet, naturalist, tax resister, surveyor, historian, philosopher, and leading transcendentalist. He is best known for his book walden. He was deeply interested in the idea of s...Henry David Thoreau was an American author, poet, naturalist, tax resister, surveyor, historian, philosopher, and leading transcendentalist. He is best known for his book walden. He was deeply interested in the idea of survival in the face of hostile elements, historical fiction change, and natural decay.