Roman Army before and after the Marius' Reforms

[Bryan]

There were more centuries for the elite because it was designed to give them an electoral edge. Same with Rural Tribes, few members compared to the more densely packed Urban Tribes, giving the elite more power even though they had fewer numbers. It was one of the reasons there was so much senatorial and equestrian dissention turning Italians into Romans following the Social War was because the original idea was to have those many millions equally distributed across all the tribes, instead of just a few urban tribes, where they ended up, which largely negated their voting power.

BTW, there were 18 centuries of Equestrian, not 12.