This thesis examines the influence of the Communist International (Comintern) on communist parties in Germany and Spain in the early years after the Russian Revolution. Specific attention is focused on the process of bolshevization, through which communists in other countries were forced to use the theory and tactics of the Bolsheviks in Russia, and the impact of this process on the March Action (1921) and German October (1923). This study questions the current historiographical dichotomy of bolshevization, which focuses on control and freedom in the relationship between the Comintern and national communist parties. Instead, the study suggests that exploring the theory and practice of bolshevization may elucidate complex realities and shed light on the influence of the Comintern on revolutionary movements.

Собачье сердце (Heart of a Dog) is a novella written in 1925 by author and playwright Mikhail Bulgakov in Moscow, USSR, later Russia. An early English translation was published in 1968. Heart of a Dog tells the story of a stray dog named Sharik, who is found by a surgeon, and undergoes extensive surgery for experimental purposes to create a New Soviet man, someone committed to the ideals of communism in the Soviet Union. In Heart of a Dog, Bulgakov satirizes the communist revolution in the Soviet Union and the concept of a New Soviet man, and criticizes the science and practice of eugenics.

Petr Kropotkin proposed the theory of Pleistocene ice age, alternative theories of evolution based on embryology, and he advocated anarchist and communist social doctrines in Europe during the nineteenth and twentieth centuries. He traveled in eastern Siberia and Manchuria from 1863 until 1867, and his subsequent publications about that area's geography became authoritative until the middle of the twentieth century. Kropotkin argued that his geographic and geologic observations in Asia, Finland, Sweden, and Canada, supported the theory of Pleistocene continental glaciation, often called the ice age. He was one of the first to study the ancient geography and climate of the Quaternary period, which spans from 2.5 million years ago until the present. Around the turn of the nineteenth century, Kropotkin offered what he said were complementary amendments to Charles Darwin's 1859 theory of evolution by natural selection. Kropotkin employed a variety of arguments from natural history, embryology, and geography to support his theory of mutual aid, which he argued was a positive mechanistic addition to the theory of evolution.