<P> There is a conception that Roman Republican cavalry was inferior to other cavalry and that they were just to support their far superior infantry . However, Philip Sidnell argues that this view is misguided and that the cavalry was a powerful and crucial asset to the Republican army . </P> <P> Sidnell argues that the record shows that Roman cavalry in Republican times were a strong force in which they bested higher reputed cavalry of the time . Examples include the Heraclea (280 BC), in where the Roman cavalry dismayed the enemy leader Pyrrhus by gaining the advantage in a bitterly contested melee against his Thessalian cavalry, then regarded as some of the finest in the Western world, and were only driven back when Pyrrhus deployed his elephants, which panicked the Roman horses . Other examples include the Equites' victory over the vaunted Gallic horse at Telamon and Sentinum, against the Germanic cavalry of the Teutons and Cimbri at Vercellae, and even against the technologically more advanced Seleucid cavalry (including some fully armored cataphracts) at Magnesia . </P> <P> A key reason for some historians' disparagement of the Roman cavalry were the crushing defeats, at the Trebia and at Cannae, that it suffered at the hands of the Carthaginian general Hannibal during the latter's invasion of Italy (218 - 6 BC) which were only rendered possible because of a powerful cavalry force . But Sidnell argues that this is only because of a consistent numerical superiority in cavalry . Another disadvantage for the Romans in the Second Punic War was that their respective cavalry were melee cavalry better suited to prodding at weak points and engaging the rear and flanks of infantry formations . This, however useful against infantry that has been routed or is flanked, failed against Hannibal's nimble, Numidian light cavalry, which used a skilful, elaborate series of movements that consistently defeated the Roman cavalry . On some occasions when they were deployed properly, led competently, and / or had the advantage of numbers or surprise, such as during the skirmish before Ilipa and at the pitched battles of the Great Plains and Zama, the Italo - Roman cavalry were able to best their Carthaginian counterparts . On occasion, such as at Dertosa, they were able to hold their own despite being supposedly outnumbered in a skirmish with Carthaginian cavalry . It should be noted that at the Zama, it was the Romans who held the numerical advantage in cavalry and the Romans had the support of thousands of renowned Numidian cavalry from their ally Massinissa . While at the Ilipa, the Carthaginian cavalry were already engaged fighting the Roman infantry before they were ambushed by the Roman cavalry from the flanks . </P> <P> The Second Punic War placed unprecedented strains on Roman manpower, not least on the over 10,000 + drachmae First Class, which provided the cavalry . During Hannibal's apocalyptic march through Italy (218 - 6 BC), thousands of Roman cavalrymen were killed on the battlefield . The losses were especially serious for the knights properly so - called (equo publico): Livy relates how, after Cannae, the gold rings of dead Roman knights formed a pile one modius (ca . 9 litres) large . In the succeeding years 214 - 203 BC, the Romans kept at least 21 legions in the field at all times, in Italy and overseas (and 25 legions in the peak year). This would have required the knights to provide 220 senior officers (120 tribuni militum, 60 decuriones and 60 praefecti sociorum). It was probably from this time that the 18 centuriae of knights became largely an officer class, while the 6,300 Roman cavalrymen required were raised from the rest of the First Class . </P>

Why did the romans place the cavalry at the sides