Almost 250 years ago the autopsy of Agustin de Ahumada y Villalon was performed by Domingo Russi, Chief Surgeon at the Royal Hospital for Natives in Mexico City. This situation will be unimportant if the former wasn't the 42nd Viceroy of New Spain; his autopsy showed a situs inversus totalis, and probably this is the first scientific report of such malformation. For many years the report by Mathew Baillie (1761-1823) of an autopsy with the same findings as the first of its kind was believed, but actually the former almost three decades earlier was performed. In 1688 Jean M. Mery (1645-1722) at the Paris Academy of Medicine gave a talk reporting autopsy findings of the same malformations. Some aspects of the life of both personages are described, the autopsy report is showed and a short history about postmortem studies are mentioned mainly those made in Spain and New Spain. Through many centuries a very close relationship has been kept and medicine has not been the exception, in the field of human pathology in the middle third of the 20th century a distinguished pathologist, Dr. Isaac Costero-Tudanca, migrated to Mexico and gave flowering to pathology and a great generation of Mexican pathologists was generated headed by Dr. Ruy Perez-Tamayo.