 Before his Oscarsborg command Eriksen had commanded the fortresses of Tønsberg, Agdenes and Bergen.Eriksen was present when Oscarsborg Fortress was returned to the Norwegian military on 12 May 1945, more than five years after it had been surrendered to the Germans, following the battle.Eriksen delivered a speech about Flag of Norway as the symbol of the fatherland, as the flag that had flown over the fortress until April 1940 was again raised over Oscarsborg.