Published online by Cambridge University Press: 24 April 2015
Gaius Marius (157-86 BC) is widely known as one of the most innovative commanders of the Roman military. In 101 BC Marius implemented an alteration to the design of the heavy legionary javelin (pilum). However, unlike Marius' previous reforms, this modification of an elemental aspect of the Roman legions was not adopted as a standard military practice. An examination of the evidence relating to the reform and of the events surrounding the time of its implementation demonstrates that the benefit of the modification was different from that currently accepted by scholars. Furthermore, the evidence indicates that the reason why this reform failed to be adopted by the legions was not that it provided no clear tactical advantage on the battlefield, but was due to the course of Roman political and military history immediately after it had first been implemented.