The original conclusion was based largely on facial reconstruction techniques and signs the skull had injuries similar to those suffered by the monarch. The new study looked at DNA instead.
It found a genetic mismatch between the head and three living male relatives of the 17th-century French king. The researchers concluded the head didn't come from anybody in the royal lineage.
Henri IV was one of France's best-loved kings, credited with bringing religious peace to the country and building Parisian landmarks like the Pont Neuf bridge during his reign from 1589 to 1610. He was the first of the Bourbon monarchs and grandfather of the Sun King Louis XIV.
The same study also found a blood sample previously attributed to King Louis XVI, one of Henri's descendants, lacked any royal ties. Louis XVI died on the guillotine during the French Revolution and many spectators reportedly soaked their handkerchiefs in the king's blood. But Cassiman and colleagues found the lingering traces of powdered blood on the handkerchief they tested did not match the Bourbon family DNA.