 Notable philosophers of the late 19th and the early 20th centuries include Vladimir Solovyev, Sergei Bulgakov, and Vladimir Vernadsky.Following the Russian Revolution of 1917 many prominent writers and philosophers left the country, including Bunin, Vladimir Nabokov and Nikolay Berdyayev, while a new generation of talented authors joined together in an effort to create a distinctive working-class culture appropriate for the new Soviet state.In the 1930s censorship over literature was tightened in line with the policy of socialist realism.