He was invited by Filippo Tommaso Marinetti and Boccioni to join the Futurist movement and was a co-signatory, with Balla, Boccioni, Carlo Carrà, and Luigi Russolo, of the Manifesto of the Futurist Painters in February 1910 and the Technical Manifesto of Futurist Painting in April the same year. He was an important link between artists in France and Italy and came into contact with Cubism before his Futurist colleagues. Following a visit to Paris in 1911, the Italian Futurists adopted a sort of Cubism, which gave them a means of analysing energy in paintings and expressing dynamism. Severini helped to organize the first Futurist exhibition outside Italy at Galerie Bernheim-Jeune, Paris, in February 1912 and participated in subsequent Futurist shows in Europe and the United States. In 1913, he had solo exhibitions at the Marlborough Gallery, London, and Der Sturm, Berlin.
Severini was less attracted to the subject of the machine than his fellow Futurists and frequently chose the form of the dancer to express Futurist theories of dynamism in art. He was particularly adept at rendering lively urban scenes, for example in Dynamic Hieroglyph of the Bal Tabarin (1912) and The Boulevard (1913). During the First World War he produced some of the finest Futurist war art, notably his Italian Lancers at a Gallop (1915) and Armoured Train (1915).In 1916 Severini departed from Futurism and painted several works in a naturalistic style inspired by his interest in early Renaissance art.After the First World War, Severini gradually abandoned the Futurist style and painted in a synthetic Crystal Cubist style until 1920.By 1920 he was applying theories of classical balance based on the Golden Section to still lifes and figurative subjects from the traditional commedia dell'arte. He became part of the "return to order" in the arts in the post-war era. Works such as The Two Pulchinellas (1922) exemplify Severini's turn toward a more conservative, analytic type of painting, which nonetheless suggests metaphysical overtones.Wikipedia