During the war the southern coast of Finland became heavily irradiated which killed all animal life including bacteria and fungus and thus effectively preserving all plants and creating the Silent Forest. Under this Silent Forest, in granite shelters, the remaining defensive forces and population has delved until very recently.
After decades of isolation, some of these shelters opened their blast doors and started exploring the remains of local civilisation. They wiped out local mutant infestation and formed a paramilitary organisation that became known as the Silent Jaegers. For many years the Jaegers held control of the southern coast. They even encountered some of the clones from Vault Outokumpu (OK) and captured them.
Things were relatively stable, until in 2140 the Jaegers looted the remains of Espoo (Esbo) Technical University in the hope of finding lost technology. The technical university had advanced research facilities in several fields and also a 6,4km deep hole for geothermic research. Damage to biochemical, biotechnological and leaks from the local test reactor had created a massive entity living in the geothermic well. This giant mutant beast with psychic powers was unleashed upon the Jaegar force and decimated them. Further expeditions to the site were cancelled. The only survivors from the encounter were mentally unstable and were mostly lost into the forests.
When the Red Peoples Army marched west, they steered clear of these these shelters and the oppressive psychic influence of the Helsinki region. However they were silently watched by the Jaegars in the Silent Forest.