Leo Nikolayevich Tolstoy (1828-1910) was a Russian novelist, essayist, and philosopher. He is widely regarded as one of the greatest authors of all time. His works, including War and Peace and Anna Karenina, are considered masterpieces of realist fiction. Tolstoy was also a moral and religious thinker, and his writings on non-violence, morality, and social justice had a profound influence on the development of pacifism and civil rights movements. He was a passionate advocate for the rights of the poor and oppressed, and his writings on the nature of human existence and the meaning of life remain relevant today.