Gabriel Seidl was the first son of Therese Seidl, daughter of the brewer Gabriel Sedlmayr and her husband, the baker Anton Seidl. He first studied mechanical engineering at the Munich Polytechnic and worked for some time as a mechanical engineer in England. There he realized that his real talent lay in the field of architecture, studied architecture at the Munich Academy (interrupted by a war service as a volunteer in the war of 1870/71). During his studies he joined the Corps Germania in 1866, as did his cousin Gabriel von Sedlmayer later. As the architect of the corps house, his portrait adorns the vestibule of the corps house together with that of Sedlmayer, as the main financier.Source and more info
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Gabriel von Seidl (born December 9, 1848 at Theatinerstraße 33 in Munich; † April 27, 1913 there) was an architect at the time and in the style of historicism.
G. Seidl had erected some buildings at Marsstrasse 28 for his own family, in which he also had his offices. In 1902 he founded the Isar Valley Association in order to limit the destruction of the Isar Valley by civilization buildings, which had already begun at that time.