What was J.K. Rowling’s pseudonym for the Cormoran Strike crime novels?

J.K. Rowling used the pseudonym Robert Galbraith for the Cormoran Strike crime novels.

The first book published under that name was The Cuckoo’s Calling in 2013. It introduced private detective Cormoran Strike and his assistant Robin Ellacott. The identity of Galbraith was initially presented as that of a former Royal Military Police investigator.

Rowling’s authorship was revealed several months after publication. The pseudonym allowed her to publish a detective novel without the immediate expectations attached to the Harry Potter name. Later Strike novels continued to appear under the Robert Galbraith name.

Robert Galbraith is not a separate co-author. It is Rowling’s pen name for this series, while the books differ in genre, setting, and characters from her fantasy novels.