From Quanta to Gravitation is a full biography of the Danish mathematical physicist Christian Møller (1904-1980) and his important contributions to quantum mechanics, particle physics, and general relativity theory. Because of his life-long association with the Niels Bohr Institute the book is also, more generally, a history of this institute and physics in Copenhagen from about 1930 to 1980. Moreover, Møller interacted with an extensive network of physicists including luminaries such as Niels Bohr, Werner Heisenberg, and Paul Dirac, and for this reason his life and career reflect major developments in international theoretical physics throughout the period. The biography is to a large extent based on archival and other unpublished material. It covers not only Møller's scientific contributions, but also his involvement in the political and organisational aspects of physics.