Is John Doe Hominem Ignotum?

How did John / Jane Doe come to be used as a placeholder name for an unknown or anonymous person in a lawsuit or death? 

The name John / Jane Doe was first used in 13th-century England, in land lawsuits. Lawyers used it as a simple, common name to fill out legal forms when the true name of a person was unknown.

I get the idea of John or Jane standing in as a ubiquitous first name but why choose Doe? Why not John Smith? Oh wait, that would be too common a name and potentially cause distress in the instance of a reported death, wouldn’t it? I suppose it works well to have a common first name and a less common last name to distinguish the term.

There is actually a fascinating history of English place holder names including: A. N. Other / Ann(e) Other, Babyboy / Babygirl, Joe Bloggs, G.I. Joe, J. Random Hacker, Joe Shmoe, John Q. Public and many more.

But what term would I choose as a placeholder name for lawsuits and corpses, if not John Doe? Maybe a Latin term for unknown person? If you wanted to say “an unknown person” in Latin you would say: hominem ignotum (human unknown). Which I may well adopt as my new email sign off.

Hominem Ignotum
Melissa Horton