The histories of the first three SS corps are well known-the actions of I, II, and III (Germanic) SS-Panzerkorps and their subordinate divisions, including the Leibstandarte SS Adolf Hitler, Das Reich, Hitlerjugend, Hohenstaufen, Frundsberg, and Nordland divisions, have been thoroughly documented and publicized. Overlooked in this pantheon is another SS corps that never fought in the west or in Berlin but one that participated in many of the key battles fought on the Eastern Front during the last year of the war-the IV SS-Panzerkorps. Activated during the initial stages of the defense of Warsaw in late July 1944, the corps, consisting of both the 3. and 5. SS-Panzer Divisions (Totenkopf and Wiking, respectively) was born in battle and spent the last ten months of the war in combat, figuring prominently in the battles of Warsaw, the attempted Relief of Budapest, Operation Spring Awakening, the defense of Vienna, and the withdrawal into Austria where it finally surrendered to US forces in May 1945. Herbert Otto Gille's IV SS-Panzerkorps was renowned for its tenacity, high morale and, above all, its lethality, whether conducting a hard-hitting counterattack or a stubborn defense in situations where its divisions were hopelessly outnumbered.