I've always been part of comedy. One of the things about our family was that if we were reasonably funny with each other, particularly my two brothers and myself, when my father was upset with something you'd want to make sure in some way you made him laugh. Because when he didn't laugh, you were in trouble!

He was interred in Fort Lauderdale's Evergreen Cemetery. In the Seattle Post-Intelligencer Nielsen pointed out that he remembers Curtiz as "a sadist a charming sadist but a sadist".

Nielsen's performance in the films Forbidden Planet and The Poseidon Adventure received positive reviews as a serious actor although he is primarily known for his comedic roles during the 1980s and the early 1990s. Nielsen made his film debut in 1956 and began collecting his roles in dramas westerns and romance films between the 1950s and the 1970s. Nielsen's portrayal of comedic characters seemingly oblivious to (and complicit in) their absurd surroundings gave him a reputation as a comedian.