The First Known Forensic Science Book Was Written in China in the 1240s

Song Ci (1186 to 1249) was an official of the Song dynasty in charge of justice, prisons and the supervision of investigations. His book Xi Yuan Lu, usually translated as Washing Away of Wrongs, gathered guidance for officials who had to work out how a person had died.

Its best-known case is a murder with a sickle. The investigator had the local men lay their sickles out in the sun. Flies gathered on only one of them, drawn by traces of blood too small to see, and its owner confessed. It is one of the earliest recorded uses of insects to solve a crime, the field now called forensic entomology.

The book also explains how to tell a drowning from a strangling, using marks on the body. Sources differ slightly on its date: Wikipedia's article on forensic science gives 1248, while many histories of the subject give 1247.