What pen name did J.K. Rowling use for her first published crime novel?

J.K. Rowling used the pen name Robert Galbraith for her first published crime novel.

The novel was The Cuckoo’s Calling, published in 2013. It introduced private investigator Cormoran Strike and his assistant Robin Ellacott. Rowling chose to publish under a male pseudonym so the books could be judged more independently from her fame as the author of Harry Potter.

The pseudonym became public after a linguistic analysis and subsequent media reporting connected Rowling to the book. Rowling later confirmed that she was Robert Galbraith, and the novels continued to be marketed under that name.

Robert Galbraith is a pen name, not a separate author. The series is often described as Rowling’s Cormoran Strike series, but its credited author remains Robert Galbraith on many editions.