The paper considers the vision of the world and the person of Józef Kazimierz Plebański (1831–1897), the Warsaw historian, one of two Polish students of Leopold von Ranke. In my article, I analyse the essential categories and objects which structure his thinking about reality, such as liberty, Providence, moral laws, state, nation, and humanity. At the end, I try to compare the worldview of Plebański with the worldview of historicism.