In 1862, the Union of Czech Mathematicians and Physicists evolved from the association of several enthusiastic students interested in selfeducation and preparation for the teaching profession. The scientific level was increased mainly by August Seydler, Mírumil Neumann and the excellent organiser František Houdek, the author of the Statute of the Union. They founded the first mathematic-physical journal in Austria. In May 1871 they organized a Congress of all mathematicians and scientists, together with an exhibition of physical instruments prepared by the chairman of the Union Dr. Neumann, assistent to professor Ernst Mach. In this article the most important steps in the early development of the Union are presented.