The creation of the "Neue Sezession" in 1910 and the inauguration of hte avant garde revue "Der Sturm" were important developments in Modern German Art. it allowed young artists and writers to express their views in the magazine and supported the two most important groups in Germany at that time: "Die Brucke" and "Der blaue Reiter". The influence of Herwarth Walden was predominant as director and organiser of the revue "Der Sturm" and the gallery of the same name. Walden was one of the first to encourage BAUER. From 1915-1921 he invited BAUER to participate in the "Sturm's" group-shows in Germany as well as abroad, and in 1917 he organised BAUER'S first one-man show in Berlin where 120 paintings were shown. The following year he wrote in his revue: "Rudolf BAUER is an artist of unqualified form and colour. By the richness of his range of colours and by the internal relationship of the infinite variety of his themes, his coloured form and fancies appertain to the organic creations. In the same way that music represents nothing but enraptures the ear of the music-lover through melody and rhythm, the works of BAUER represent nothing recognisable by intelligence or conceivable by an association of souvenirs. They allow those who look at the paintings by their form and colour to participate in an inner vision".
This period which began in 1910 and reached its peak in 1919 is lyric expressionism but it is already completely abstract. Its violent colours and characteristic stripes are very similar to those works of Kandinsky of the same period. Like Kandinsky, BAUER directed his talents towards the geometrical construction which he was to develop until the end of his life. Kandinsky's art was transformed towards 1919 under the influence of the totally non-figurative tendencies of Russian art (Rayonism and Suprematism). Even if BAUER was not the first to accomplish this turning-point of abstract expressionism towards geometrical abstraction, he certainly followed Kandinsky very closely to the ponit that when Solomon R. Guggenheim started to form his collection for the Guggenheim Foundation, New York, in 1935-36, he bought together with paintings by Kandinsky, Leger Mohoy-Nagy, Chagall, Klee, Delauney, Modigliani and Seurat, 100 paintings by BAUER.
The first exhibition of the Guggenheim collection was held in 1936 at the Charleston Museum in South Carolina and the following year at Philadelphia under the auspices of the Philadelphia Art Alliance. From 1937 until the end of his life in 1953 BAUER lived in the United States.