[2] Without being a member of the Reichstheaterkammer [de], he was engaged as head director at the houses in Theater Bielefeld and from 1939 in the Wrocław Opera.
Even after the theatre was destroyed in the course of Allied air raids on Halle, he remained connected to the city.
At the Staatliche Hochschule für Theater und Musik Halle [de], he became a professor in 1951 and was head of the opera direction department,[3] a course of study established for the first time in Germany.
He built up a Handel collective, for which he brought the conductor Horst-Tanu Margraf and the stage designer Rudolf Heinrich to Halle.
He was there until 1958[4] engaged as director and head of the young talent studio at the Komische Oper Berlin.
[1] After Hans Pischner took over as director of the Staatsoper in 1963 and set other priorities, Rückert concentrated on guest productions in Leipzig and Frankfurt/Oder.
Musicology and music criticism, however, turned to new ways of performance, so that he withdrew more and more artistically even in the course of an illness.
In 1948, Rückert staged the premiere of the chamber opera Die Nachtschwalbe by Boris Blacher.