The previous responder is correct. The husband dominated a household, while the wife was simply a helpmate of the husbands.
Focus on the last scene of the play. Nora leaves, closing the door behind her. That closing door is one of the most iconic moments in the theater. It represents her refusal to be a mouse under her husband, and her striking out on her own.
Everything prior to that moment leads up to that act of departure.
This play was way ahead of its time. We accept women’s equality today, but at the time of the play the idea was new.