Some comments to the History of Valuation Theory Peter Roquette (Heidelberg) Abstract On February 9, 1931 Wolfgang Krull wrote a letter to Helmut Hasse, explaining his new ideas for a generalization of the classical notion of valuation. This led to Krull's great paper, published in the Hensel dedication volume of Crelle's Journal, which started a new era of valuation theory. We shall discuss Krull's ideas, their roots in the past, and the first steps to explore the structure of Krull valuations as well as the range of their applications. The time period covered will be roughly 1930 -- 1950. We regard our contribution as the beginning of a future ``Part 2'' of the History of Valuation Theory, Part 1 having appeared in the Saskatoon proceedings (volume 1) already.