Concentration camps built by nazis in 1933 initially held

political prisioners

Explanation:

During the 1930's German citizens witnessed the removal of people adscribing to different ideas like ; Communists, Social Democracy, Jewish practicants.

The practice of dissapearing people for political reasons began to be widespread in 1933 as former citizens were excluded from their civil and human rights.

They were often the scapegoats and considered undesired in society. The justification was often that they were enemys of the state, that they had plunged Germany into the crisis. The systematically practice of removing the people from their natural rights then potrayed them as non humans who only deserved to work unwillingly or die.

for your : )

i think they would live in caves or natural tunnels