Early life
Otto Colosser was born on 8 November 1878 in the gemeinde of Schöneberg, to an evangelical Protestant family. Schöneberg was a newly created municipality; earlier that year, the gemeinden of Alt-Schöneberg and Neu-Schöneberg merged. He graduated from the Charlottenburger oberrealschule, before attending Charlottenburger's technical university, where he studied structural engineering. After graduating, he became employed as an architect in line with his degree. In 1910, Colosser changed professions, after taking control of his father's business.
In 1914, the First World War began, once again changing Colosser's profession. He initially joined the Landsturm, assisting with military construction. During his service, he became a site manager in Building Department III, due to his architectural experience. In 1916, he began directing the construction of large-scale ammunition factories. However, in 1919, the First World War ended with a German defeat, and with it Colosser's employment.
When the Economic Party was created in 1920 by Hermann Drewitz and Johann Viktor Bredt, among others, Colosser would join the party the same year it was created. He would rise to become deputy party chairman by 1924, remaining in this position until his resignation from the party in 1931; he would further serve the party as chief propagandist from 1924 to 1930. As a member of the Economic Party, he would serve in a series of representative positions: as Stadtverordneter of the Berlin City Council from 1925 to 1927, member of the Landtag of Prussia from 1927 until the Prussian election the following year, and as a national Reichstag deputy from 1928 to 1932. He participated in numerous professional associations within the construction sector, notably serving on the executive board of the German Craftsmen's Association.
Colosser Affair
In November 1930, following Carl Ladendorff's attempts to reduce party chairman Hermann Drewitz's control of the Economic Party, Colosser first accused — and in the following month — launched charges against Drewitz for embezzlement. In January of the next year, Drewitz was retained as party leader by the party's leadership, with investigations by a party court pending. In March, Drewitz was exonerated of the embezzlement allegations, soon followed by decisively winning re-election as party leader. Concurrently, the party leadership began expulsion procedures against Colosser, leading to his resignation from the Economic Party. He would join the German State Party, a centrist liberal party.
According to Social Democratic Party of Germany-affiliated newspaper Vorwärts, on 25 January 1931, Colosser filed a formal legal complaint against Drewitz, alongside the internal party dispute. He accused Drewitz of similar allegations to those he submitted to the Economic Party's leadership: embezzlement, fraud, and breach of trust. However, on 25 August, the regional Generalstaatsanwalt discontinued the legal proceedings; Colosser's legal challenges against Drewitz ended.
