Lenin (22 April [O.S. 10 April] 1870 – 21 January 1924) was a Russian communist revolutionary, politician and political theorist. Held in high esteem as a founding father of the Soviet Union until its dissolution in 1991, he remains an ideological figurehead behind Marxism-Leninism and a prominent influence over the international communist movement.

Mohandas Karamchand Gandhi (2 October 1869 – 30 January 1948) was the preeminent leader of Indian independence movement in British-ruled India. Employing nonviolent civil disobedience, Gandhi led India to independence and inspired movements for civil rights and freedom across the world.  Indians widely describe Gandhi as the father of the nation.His birthday, 2 October, is commemorated as Gandhi Jayanti, a national holiday, and world-wide as the International Day of Nonviolence.

Mao Zedong (December 26, 1893 – September 9, 1976) commonly referred to as Chairman Mao is regarded as one of the most important individuals in modern world history. He was a Chinese Communist revolutionary, the founding father of the People's Republic of China, a theorist, military strategist, poet, and visionary who was responsible for driving imperialism out of China, modernizing China and building it into a world power, 

Erich Seligmann Fromm (German: [fʀɔm]; March 23, 1900 – March 18, 1980) was a German social psychologist, psychoanalyst, sociologist, humanistic philosopher, and democratic socialist. He was associated with the Frankfurt School of critical theory.

Karl Marx (5 May 1818 – 14 March 1883 )was a philosopher, economist, sociologist, journalist, and revolutionary socialist. Born in Germany, he later became stateless and spent much of his life in London. He is one of the most influential figures in human history. 

Fidel Alejandro Castro Ruz (born August 13, 1926) is a Cuban politician and revolutionary. Politically a Marxist-Leninist and Cuban nationalist, he is decorated with various international awards, with his supporters lauding him as a champion of socialism, anti-imperialism, and humanitarianism, whose revolutionary regime secured Cuba's independence from American imperialism.