One of the Roman legionary's most valuable pieces of equipment was the gladius, which is:
A javelin
A shield
A helmet
A short sword
A breastplate
A short sword. One of the Roman legionary's most valuable pieces of equipment was the gladius or short sword. Borrowed from the Spanish, the gladius had many variations throughout the years, but remained a standard melee weapon of the Roman soldier. However, all of the equipment mentioned (short sword, javelin, shield, helmet and body armor), combined with sound logistics, steady pay and strenuous training, contributed to the Roman legions' effectiveness.