Henri Rousseau is a self-taught master, cornerstone of Naïve Art (Primitivism), and vital precursor to Surrealism. Nicknamed "Le Douanier" (the customs officer), he rendered dreamlike, exotic jungles and enigmatic scenes with intense poetic clarity. His signature style features flattened perspective, sharp contours, bold color blocks, and a hypnotic atmospheric stillness. Dismissed by the Academic establishment, Rousseau gained profound acclaim among the Parisian avant-garde—including Pablo Picasso and Guillaume Apollinaire—who revered his raw, unmediated artistic vision.