Søren Kierkegaard was a Danish philosopher born in 1813, often considered the father of existentialism. He focused on individual experience and the importance of personal choice, emphasizing that each person must find their own meaning in life. His works explore themes like faith, anxiety, and the nature of existence. Kierkegaard wrote extensively, using pseudonyms to present different viewpoints. His notable works include Fear and Trembling and Either/Or. He influenced many later thinkers, including Friedrich Nietzsche and Jean-Paul Sartre, and his ideas continue to shape discussions in philosophy, theology, and psychology today.