In the August 2000 issue of "Military Heritage", Steven Weingartner said
"The gladius accounts for more deaths than any other weapon prior to the advent of firearms."

Pause for thought...

The support for this is that no other kind of weapon remained so
consistently the same in design as the gladius for so many years.
Bows, axes, spears and so on all changed over time but the gladius remained fixed apart from minor variants for around 400 years as the weapon of choice for the Roman Empire.

Find out a little more about the gladius.