Leonardo Divinci was the oldest that I heard of that cut into flesh to learn how the body works under threat of being put to death himself under harasies, He also made the first artificial heart.
Forensic Anthropology is a combination of physical anthropology and human osteology in a legal setting. It is used in criminal cases for identification of deceased individuals, who have decomposed or disfigured bodies. Forensic Anthropology first came into use in the 11th century. It is based on the first written account of using forensic Anthropology and other branches of Forensics, in criminal cases in a book called Collected cases of Injustice Rectified which was written by Song Ci in 1247.
I have not found a definite date...it evolved over time.