Aside from plays, what other form of literature did Henrik Ibsen write?

Henrik Ibsen also wrote quite a bit of poetry.

Although he was mostly known for his plays (some of which are A Doll's House, Hedda Gabler, Ghosts, etc.) he also wrote poems, although they weren't as famous as his plays. After Shakespeare, his plays have been the most frequently performed ones during the 20th century. He was a celebrated Norwegian playwright and poet who wrote during the 19th century (he died in 1906).

Henrik Ibsen was more than a playwright. In addition to writing plays, he wrote a great amount of poetry. He was nominated for the Nobel Peace Prize a total of 3 times. He was also a well-known theatre director in his time.