Please note that Mommsen uses the AUC chronology (Ab Urbe Condita), i.e. from the founding of the City of Rome. You can use this reference table to have the B.C. dates
The strict conception of the unity and omnipotence of the state in
all matters pertaining to it, which was the central principle of the
Italian constitutions, placed in the hands of the single president
nominated for life a formidable power, which was felt doubtless by the
enemies of the land, but was not less heavily felt by its citizens.
Abuse and oppression could not fail to ensue, and, as a necessary
consequence, efforts were made to lessen that power.
It was,
however, the grand distinction of the endeavours after reform and
the revolutions in Rome, that there was no attempt either to impose
limitations on the community as such or even to deprive it of
corresponding organs of expression--that there never was any
endeavour to assert the so-called natural rights of the individual in
contradistinction to the community--that, on the contrary, the attack
was wholly directed against the form in which the community was
represented.