One can get some insight into Kronstein’s importance from Professor Tony A. Freyer’s Antitrust and Global Capitalism, 1930–2004. Here is more:
Heinrich Kronstein, born in Germany in 1897, left Germany with his family in late November of 1935 and headed to New York, leaving behind a flourishing law practice. In New York he quickly embarked on a new career in both law and academia, enrolling in Columbia Law School to obtain his American LLB degree. Towards the end of his third year, he was noticed by A. A. Berle, a renowned professor of corporation law at the law school who was headed for a wartime job as Undersecretary of State. Berle arranged for Kronstein to get a job in the Department of Justice starting in1939.
In 1942 Kronstein applied to Thurman Arnold to move over to the Antitrust Division of the Department of Justice to conduct an intensive study of German cartels. Upon arriving at the Antitrust Division, Kronstein soon became referred to as the Chief Adviser to the Department of Justice on international cartels, while also acting as an advisor to Undersecretary of State Berle and to Agriculture Secretary Henry Wallace.
In August 1945, shortly after the war with Germany ended, at the behest of some high level US official Kronstein travelled to Frankfurt to work on German reconstruction and the formation of a new Government in Hessen. He was able to make a major contribution in helping to select the first democratic government of Hessen.
Kronstein returned to DC in November of 1945 but remained active in German rebuilding efforts. He left the Department of Justice in 1946 to become a professor full-time at the Georgetown University Law School but continued this work under the auspices of some US agency. In a memo in 1946 he noted the adverse German reaction to proposed anti-cartel laws.Interested parties should contact Don Wallace, Jr., who is an emeritus professor of law at Georgetown University Law Center and Chairman of the International Law Institute, at wallace@ili.org
Nonetheless Kronstein, then also a professor of law at the Frankfurt University, threw himself in with full vigor to move Germany, and later Europe, to the adoption of anti-cartel laws. This included memos on the American antitrust laws, a 355 page report on the US FTC for the German Economics Ministry, and correspondence with the German Economics Minister. Later on, when the proposed EU anti-cartel regulations came into play in 1957, Kronstein wrote a detailed letter to its President, Walter Hallstein.
After the adaption of the anti-cartel laws by the German parliament, Kronstein was called upon to speak before various academic and governmental bodies about the proposed adoption of the European cartel laws, including a cartel conference in Frankfurt which was attended by all the stars in the field, congressional committees, and the preparation of a statement for OECD (Organization for Economic Cooperation and Development) in Paris as well as a report at the International Conference on Monopolies in Cambridge in 1969. In 1967, Kronstein published, first in German and then in English, a book entitled "International Cartels" using his knowledge and reputation in the field to produce this final landmark.