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The Hamburg School of Astrology originated in Hamburg, Germany, and revolved around the research and teachings of surveyor/astrologer/amateur astronomer Alfred Witte. The term Hamburg School as an astrological method  originated in 1923 at the Second German Astrological Congress in Leipzig, Germany.
The Hamburg School was established as an Association as "Astrologenverein Hamburger Schule" on October 31, 1925 at 9h45'51" PM (-1 = GMT), in Hamburg/Germany. In 1932 the first partner group was established in Düsseldorf/Germany by Theodor Keysers.
Early collaborators of Alfred Witte were Friedrich Sieggrün and Ludwig Rudolph. In a search for planets beyond Neptune (Pluto had yet to be discovered), Witte claimed four hypothetical trans-Neptunian planets, and in 1927 Sieggrün claimed yet another four. None of the these planets were astronomically verifiable. Witte named his planets Cupido, Hades, Zeus and Kronos. Sieggrün expanded the list planets with Apollon, Admetos, Vulkanus and Poseidon.
Ludwig Rudolph printed and published Witte's claims, the core of which were published in the Rulesbook for Planetary Pictures (Regelwerk für Planetenbilder) in 1928. An increasing amount of the research of the Hamburg School revolved around astrological midpoints and use of the extra planets.
Witte and Rudolph were pursued by the Gestapo as enemies of the Third Reich. Witte committed suicide before he could be sent to a concentration camp, and Rudolph was interned, the Rulebook for Planetary Pictures banned and burned by the Nazis.
Reinhold Ebertin, a student of Hamburg School methods, eliminated the use of the hypothetical planets while maintaining the core teachings of the Hamburg School, renamed it "Cosmobiology" (German: Kosmobiologie), and published it in The Combination of Stellar Influences in 1940, last updated in English in 1972.
After the fall of the Third Reich, the Hamburg School reconvened, and Ludwig Rudolph played the key role in perpetuating the teachings of the Hamburg School. The Hamburg School astrologer Hermann Lefeldt combined Witte's theories with more astrological traditions such as the use of astrological houses. However, other Hamburg practitioners maintained their focus on working only with astrological midpoints , abandoning traditional practices, including the 12 houses and rulerships.
Associations of Hamburg School Astrology (inactive)
- Astrological Association "Hamburg School", German: Astrologenverein "Hamburger Schule", Hamburg/Germany, est. 1925
- Witte Study Group Düsseldorf, German: Witte-Studiengemeinschaft Düsseldorf, Düsseldorf/Germany, est. 1932
- Uranian Astrology Research Club, Cleveland, Ohio/USA, 1939
- Astrological Study Society (Hamburg School), German: Astrologische Studiengesellschaft (Hamburger Schule), Hamburg/Germany, est. 1947
- The Bangkok Astrological School, Bangkok/Thailand, est. 1972
Associations of Hamburg School Astrology (active)
- The Uranian Society, New York City/USA, est. 1985
- The International Uranian Fellowship, The Hague/Netherlands est. 2007
- L.Rudolph, Witte: "Regelwerk für Planetenbilder von Alfred Witte - Die Astrologie von morgen", 1st Edition, Witte-Verlag Ludwig Rudolph, 1928/1929
- L.Rudolph, Witte: "Regelwerk für Planetenbilder von Alfred Witte - Die Astrologie von morgen", 2nd Edition, Witte-Verlag Ludwig Rudolph, 1932.
- L.Rudolph, Witte: "Regelwerk für Planetenbilder von Alfred Witte - Die Astrologie von morgen", 3rd Edition, Witte-Verlag Ludwig Rudolph, Hamburg 1935.
- First official English translation by Richard Svehla as: "Rulesbook for Planetary Pictures by A.Witte & L.Rudolph", Phoenix Bookshop, Cleveland/Ohio, USA 1939, Reprint 2014
- Perpetual Ephemeris: Witte, Alfred: "Immerwahrende Ephemeride fur [...]Cupido, Hades, Zeus und Kronos [...]", Special Edition from "Regelwerk...", Witte-Verlag Ludwig Rudolph, Hamburg 1935.
- Witte, Alfred: "Der Mensch - eine Empfangsstation kosmischer Suggestionen", compiled and commented by Hermann Sporner und L.Rudolph, Ludwig Rudolph (Witte-Verlag), Hamburg 1975.
- Schnitzler, Ilse: "Lexikon für Planetenbilder", Ludwig Rudolph (Witte-Verlag), Hamburg 1957.
- L.Rudolph, H.Lefeldt: "Witte: Regelwerk für Planetenbilder", Ludwig Rudolph (Witte-Verlag), Hamburg. Editions: 1946-50, 1959, 1983, 2012
- Second official English translation as: "Rulesbook for Planetary Pictures", Ludwig Rudolph (Witte-Verlag), Hamburg 1974, USA 1990
- Brummund, Ruth: "Astropsychologische Charaktermerkmale", Ludwig Rudolph (Witte-Verlag), Hamburg 1972.
- Brummund, Ruth: "Regelwerk-Neufassung", Udo Rudolph Verlag, Hamburg 1990.
- Friedrich Sieggrun in the lecture "Arbeitsmethoden der Hamburger Schule" (Methods of Hamburg School), July 2, 1923, at the Second German Astrologer Congress 1923.
- The "2.2. The names "Hamburg School" and "Uranian System of Astrology" ", Lecture "The Hamburg School (The early years)" by Michael Feist, p.9
- Founding of Astrologers Association »Hamburger Schule« report by Ludwig Rudolph, 1925. Published in "Nachrichtenblatt" no. 9-10, p. 94, Dec. 1925/26
- The "2.7. Witte Study-Community", Lecture "The Hamburg School (The early years)" by Michael Feist, p. 12
- "The New German Astrology (Hamburg School)" and "The New Uranian Astrology", lectures by Svehla at the All-American Astrological Convention in Chicago, 1936.
- "Preface of reprint" "Rulesbook for Planetary Pictures by A.Witte & L.Rudolph", p. 10, Reprint of the first English translation 1939. Witte-Verlag Publishing, Hamburg, 2014
- The association was re-founded as “Astrologische Studiengesellschaft (Hamburger Schule)” , engl. “Astrological Study Society (Hamburg School)”, December 27th, 1947, 6:38 PM (GMT), in Hamburg, by Ludwig Rudolph, Johann Rose, Hermann Lefeldt, Werner Ritter, Heinrich Schacht, Friedrich Heeger, Albert Berndt, Otto Wilms and Willi Hellberg. References: cover pages and articles in the Journal “Hamburger Hefte” 4/1998 and 3/1999. (In the 1960s, Otto Wilms introduced the "Hamburg School" method in Australia.)
- Extended Version based on the 3rd Edition by A.Witte & L.Rudolph. The 4th Edition by Herman Lefeldt and Ludwig Rudolph included the Transneptunians by Friedrich Sieggrun for the first time.