SS officer Reinhard Heydrich originally formed the basis and ideology of the SS werewolves, realising Hitler would never surrender until the bitter end, he then knew that there should be at least a basic continued resistance against the Allies after the war. However Heydrich was killed in 1942, therefore Himmler started acting in 1943. Cues and studies were intensely taken from anti-Nazi guerrillas in Germany's occupied lands, workers from concentration camps were put to good use creating networks of tunnels throughout Germany and Austria. Stockpiling of weapons, explosives, food and water were undertaken. Specific men from the SS were brought back from the front lines so they could be trained as partisan-guerrillas.
The Werewolves struck immediately the next day after Germany surrendered, their attack was symbolic as well as terrorising. Their first attack was against the occupied Reichstag, assaulting the Soviet soldiers outside and within the buildings reaching the top they threw off the Red Soviet banner and replaced it with the Swastika before retreating having successfully killed 45 Soviet troops as well as symbolically retaking the Reichstag. They then moved throughout the destroyed city employing hit and run tactics as well as freeing prisoners of war and women who were about to be raped. Moving throughout the ruined city, hitting Soviet troops everywhere they met them, after extreme damage had been inflicted the Werewolves disappeared into the tunnels and had successfully won what the Russians later called "The Second Battle of Berlin".
The Allies and especially the USSR were shocked to find that there were still German soldiers active in fighting however they didn't treat this as an insurgency, rather they looked upon it as merely surviving die-hard Nazi troops who wanted go down fighting. Troop strength was increased and the Soviets for handing reprisals killed every ten Germans for one Russian soldier killed. Slowly men, women and even children soon began smuggling themselves underground to participate in the insurgency, increasing the numbers and capabilities of the werewolves. On March 6th they attacked American troops patrolling a sector in Western Germany killing 25 soldiers, on March 16th they hit a British supply truck killing five soldiers, on March 20th they ambushed a Soviet convoy heading to Berlin killing 33 men and injuring dozens more. These successful attacks now put in the minds of the Allies that they were dealing with a full-scale insurgency led by professional soldiers not rebellious civilians.