He was appointed professor of history at Königsberg in 1913, Marburg in 1920, and Berlin in 1922.[2] In 1929 he became the director general of the Prussian Privy State Archives, in Berlin-Dahlem.[3] In connection with accepting the position he advocated for the establishment of a special Institute for Archival Sciences and Historical Training (Preußisches Institut für Archivwissenschaft), to provide for the professional training of archivists; the institute, which came under the administration of the state archives, opened in Berlin-Dahlem in May 1930.[3][4] Brackmann, in his capacity as director general of the archives, simultaneously served as the archival institute's first director, until his retirement in 1936.[5] During his term at the archives he retained an honorary professorship at the University of Berlin.[2]