During World War II, in 1941, as soon as the German forces occupied Yugoslavia, Bishop Nikolaj was arrested by the Nazis in the Monastery of Žiča, after which he was confined in the Monastery of Ljubostinja. Later he was transferred to the Monastery of Vojlovica (near Pančevo) in which he was confined together with the Serbian Patriarch Gavrilo V until the end of 1944. On 15 September 1944, both Serbian Patriarch Gavrilo V (Dožić) and Bishop Nikolaj were sent to Dachau concentration camp, which was at that time the main concentration camp for clerics arrested by the Nazis. Both Velimirović and Dožić were held as "special prisoners" ("Ehrenhäftlinge") imprisoned in the so-called "Ehrenbunker" (or "Prominentenbunker") separated from the work camp area, together with high-ranking Nazi enemy officers and other prominent prisoners whose arrests had been dictated by Hitler directly.