 In Berlin, Guardini had introduced her to Kierkegaard, and she resolved to make theology her major field.At Marburg (1924–1926) she studied classical languages, German literature, Protestant theology with Rudolf Bultmann and philosophy with Nicolai Hartmann and Heidegger.Arendt arrived at Marburg that fall in the middle of an intellectual revolution led by the young Heidegger, of whom she was in awe, describing him as "the hidden king [who] reigned in the realm of thinking".