Roman army of the mid-Republic placed unprecedented strains on Roman manpower, not least on the Order of Knights and the First Class of commoners which provided the cavalry. During Hannibal's apocalyptic march through Italy (218–216 BC), thousands of Roman cavalrymen were killed in the field. The losses were especially serious for the equestrian order, which also provided the army's senior officers. Livy relates how, after Cannae, gold rings (a badge of knightly rank), recovered from the corpses of Roman knights formed a pile one "modius" (about 9 litres) large. In the succeeding years 214–203 BC, the Romans kept at least 21 legions in the field
Socii to raise a double-strength army of four legions and four "alae" e.g. at the Battle of Cannae in 216 BC, where each Consul commanded an army of about 40,000 men. Polybius states that the Romans and their allies could draw on a grand total of 770,000 men fit to bear arms (of which 70,000 met the property requirement for cavalry) in 225 BC, shortly before the start of the Second Punic War. The Romans reportedly asked their allies for an urgent register of all "men fit to bear arms" for a "tumultus Gallicus". Polybius' subtotals, however, are garbled, as he