Futurism was an artistic and social movement that originated in Italy, and to a lesser extent in other countries, in the early 20th century. It emphasized dynamism, speed, technology, youth, violence, and objects such as the car, the airplane, and the industrial city. Its key figures included Italian artists Filippo Tommaso Marinetti, Umberto Boccioni, Carlo Carrà, Fortunato Depero, Gino Severini, Giacomo Balla, and Luigi Russolo. Italian Futurism glorified modernity and, according to its doctrine, "aimed to liberate Italy from the weight of its past." Important Futurist works included Marinetti's 1909 Manifesto of Futurism, Boccioni's 1913 sculpture Unique Forms of Continuity in Space, Balla's 1913–1914 painting Abstract Speed + Sound, and Russolo's The Art of Noises (1913).