Yes. The Independent State of Croatia was formed by Hitler and lead by the fascist Ustaše regime. They built several concentration camps in order to exterminate Serbs, Jews, Roma and antifascist Croats. The most infamous of them all was Jasenovac camp where at least 100.000 people died, mostly Serbs.
However, it is worth noting that the Ustaše regime was not a democratically elected government of Croatia and that most Croats joined the antifascist partisan movement against the Ustaše regime.
Former Answer:
The Nazi puppet state of Croatia was steeped extreme nationalism and in superficial (Roman Catholic) religiosity. It was characterized by a deep seated hatred of the Serbs and of course the Jews. The Croatian government of the day needed no prompting from the Nazis to commit mass murder.
Concentration camps.
According to research reports, Nazis actually set up 20 000 concentration camps.
Concentration camps.
They were chosen from within the SS staff at concentration camps.
The Nazis.
10000
Concentration camps, Extermination camps and Death camps
othing
yes
All the countries which were not invaded by the Nazis including Britain didn't have any Concentration Camps.
not as a direct consequence
they flee or died