Complex sentence: The Warsaw Uprising started on 1 August 1944 and changed Himmler's plans on August 4,1944 a combat ready regiment of the brigade was ordered to assist the efforts in crushing the rebellion.
Split into simpler sentences: The Warsaw Uprising started on 1 August 1944 and changed Himmler's plans. On August 4,1944 a combat ready regiment of the brigade was ordered to assist the efforts in crushing the rebellion.