Nazi objectives for creating a system of KL pretty much defined its victims:
- Leaders, functionaries and influential members of political parties – Communists, Social-Democrats, Catholics, Conservatives, etc.
- Active and potential members of Resistance groups not affiliated with any political party (i.e. members of the elites of German-occupied nations)
- Influential Christians (priests, monks, nuns, lay officials, theologians etc.) who publicly oppose and criticize Nazi regime
- Members of religious groups openly opposed to Nazism (Jehovah Witnesses, etc.)
- Individuals (i.e. not affiliated with any group) engaged in violent or non-violent protests – from journalists to terrorists
- Career (habitual) criminals
- Homosexuals (oddly, the Nazis persecuted almost exclusively male homosexuals, leaving lesbians pretty much alone)
- Prostitutes, pimps, brothel owners and others engaged in providing sexual services
- “Asocials” – trumps, homeless, vagrants, “work shy”, beggars, etc.
How many KL were there? The honest answer is: we do not know (and might never know). Estimates range from 1,200 (probably too low) to a whopping 42,500 (way too high; however the latter include Jewish ghettos).
How many individuals were interned in KL at some point in their lives? We have no idea. It is estimated that in January of 1945 there were about 715,000 inmates in all camps both inside and outside Germany (far less than there were in Gulag at its peak). But whether this number includes all inmates, we do not know (at that time statistics in Germany was not exactly accurate).
How many died in the camps – murdered or succumbed to hunger, diseases, etc. We have no clue. One estimate puts the total number of death at (IMHO, realistic) half a million but how accurate is this estimate?
In short, we only know that we do not know – and probably will never know. Most likely, the total number of inmates at least once incarcerated in KL was in single-digit millions (with the overwhelming majority coming from occupied territories) and the death toll is around one million or less.