What pen name did J.K. Rowling use for her crime novels?

J.K. Rowling used the pen name Robert Galbraith for her crime novels.

The Robert Galbraith name was introduced with The Cuckoo’s Calling, a crime novel published in 2013. The book initially appeared to be by an unknown new author. Its true authorship was later revealed to be Rowling, creating substantial publicity around the series.

Rowling chose a separate identity so the books could be judged without the immediate expectations attached to her Harry Potter fame. Robert was reportedly inspired by Robert F. Kennedy, while Galbraith was connected with Rowling’s interest in names and personal associations.

The novels featuring private detective Cormoran Strike are published under the Galbraith name. Robert Galbraith is therefore an author pseudonym, not a fictional detective or a character within the stories.