The “K” in J.K. Rowling’s published name came from her grandmother Kathleen.
Rowling was born Joanne Rowling and did not originally have a middle name beginning with K. When Bloomsbury prepared to publish Harry Potter and the Philosopher’s Stone, the publisher believed a name with two initials might appeal to a broad audience. Rowling chose Kathleen as the second initial in honor of her paternal grandmother.
The name therefore does not stand for “Katherine Rowling,” a common assumption among readers. Rowling’s legal name has also changed over time through marriage, but J.K. Rowling remained her best-known professional name. The use of initials helped create a distinctive author identity at the beginning of the Harry Potter series.
In the United States, the first book was marketed under the name J.K. Rowling even though the title changed to Harry Potter and the Sorcerer’s Stone. Later editions, biographies, and reference works continued to use the initials, making them inseparable from the author’s public identity.