After the arrival of the Zheronians in 1940, and the successful completion of Operation Sealion and Operation Barbarossa, Himmler was opposed to Reich cooperation with the aliens, on the principal that the "Master Race" should operate on its own without dependence on other powers. In 1959, Himmler's vision was partially realized with the construction of the Reichsraumschiff Reichsadler on the Venusian port of Ludendorff.
Over the decades, Himmler became more and more disgusted with Hitler's cooperation with the alien Zheronians. In conjunction with Arabian caliph Haj Amin al-Husseini, Himmler and the SS launched the SS coup of 1961, launching an invasion of Berlin, resulting in the monthlong Siege of Berlin. Ultimately, Himmler was captured on his flagship, the Reichsraumschiff Herrenvolk, by a team led by Otto Skorzeny. Himmler was then killed on the spot.