Henri Rousseau was a French Post-Impressionist artist who is best known for his jungle scenes. He was born in 1844 and died in 1910. He was self-taught and worked as a toll collector before becoming an artist. He was nicknamed 'Le Douanier' (the customs officer) due to his occupation. His works are characterized by their bright colors, flatness, and dreamlike quality. He is considered one of the most influential artists of the 20th century.