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
From: The History of Rome, by Theodor Mommsen
Translated with the sanction of the author by William Purdie Dickson
It is still more remarkable, that Crassus on the same occasion made preparations to enrol Egypt and Cyprus in the list of Roman domains,(10) and that Caesar about the same time (689 or 690) got a proposal submitted by some tribunes to the burgesses to send him to Egypt, in order to reinstate king Ptolemaeus whom the Alexandrians had expelled.
10. Plutarch, Crass. 13; Cicero, de Lege agr. ii. 17, 44. To this year (689) belongs Cicero's oration -de rege Alexandrino-, which has been incorrectly assigned to the year 698. In it Cicero refutes, as the fragments clearly show, the assertion of Crassus, that Egypt had been rendered Roman property by the testament of king Alexander. This question of law might and must have been discussed in 689; but in 698 it had been deprived of its significance through the Julian law of 695. In 698 moreover the discussion related not to the question to whom Egypt belonged, but to the restoration of the king driven out by a revolt, and in this transaction which is well known to us Crassus played no part. Lastly, Cicero after the conference of Luca was not at all in a position seriously to oppose one of the triumvirs.
These machinations suspiciously coincide with the charges raised by their antagonists. Certainty cannot be attained on the point; but there is a great probability that Crassus and Caesar had projected a plan to possess themselves of the military dictatorship during the absence of Pompeius; that Egypt was selected as the basis of this democratic military power; and that, in fine, the insurrectionary attempt of 689 had been contrived to realize these projects, and Catilina and Piso had thus been tools in the hands of Crassus and Caesar.
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