Most white émigrés left Russia from 1917 to 1920 (estimates vary between 900,000 and 2 million), although some managed to leave during the 1920s and 1930s or were expelled by the Soviet government (such as, for example, Pitirim Sorokin and Ivan Ilyin). They spanned all classes and included military soldiers and officers, Cossacks, intellectuals of various professions, dispossessed businessmen and landowners, as well as officials of the Russian Imperial government and of various anti-Bolshevik governments of the Russian Civil War period. They were not only ethnic Russians but belonged to other ethnic groups as well.