In 2010, a team of researchers used facial-reconstruction techniques to conclude that it was indeed "Good King Henry," who was assassinated in 1610. The case seemed closed.
Now, a second team of scientists says it can't be the royal head, since DNA tests do not match Henry's living descendants.
Researchers for the second study wrote to the British Medical Journal this week urging a retraction of the earlier study, and two members of the 2010 team agree that their conclusions may have been faulty.
But Philippe Charlier, the lead researcher from 2010, maintains the results are still valid. He said DNA results are useless, in part because the French royals were philanderers.
"It is hopeless to try to match a family tree and a series of genetic links [over] such a long period," Charlier said. Until the debate dies down, the mummified head is resting in a bank vault in Paris.