Judge Dee (also, Judge Di) is a semi-fictional character based on the historical figure Di Renjie, county magistrate and statesman of the Tang court. The character first appeared in the 18th-century Chinese detective and gong'an crime novel Di Gong An. After Robert van Gulik came across it in a second-hand book store in Tokyo, he translated the novel into English and then used the style and characters to write his own original Judge Dee historical mystery stories.