|The numbering of the letters and the summary of Cicero's activities for this year are taken from Cicero, Letters, ed & trans by Evelyn Shuckburgh.
This was the year in which Caesar, returning from his propraetorship in Spain, found Pompey in difficulties with the senate (1) as to the confirmation en bloc of his acta in the East, (2) as to the assignation of lands to his veterans; and being met with opposition himself as to the triumph that he claimed, and his candidatureship for the consulship, he formed with Pompey and Crassus the agreement known as the first triumvirate. Cicero saw his favourite political object, the concordia ordinum, threatened by any opposition to the triumvirate, which he yet distrusted as dangerous to the constitution. We shall find him, therefore, vacillating between giving his support to its policy or standing by the extreme Optimates. P. Clodius is taking measures to be adopted into a plebeian gens, in order to stand for the tribuneship. Quintus is still in Asia. Pompey's triumph had taken place in the previous September.
- XXIII: To Atticus in Epirus, from Rome, 20 January
- XXIV: To Atticus in Epirus, from Rome, 15 March
- XXV: To Atticus in Epirus, from Rome, 13 May
- XXVI: To Atticus in Greece, from Rome, June
- XXVII: To Atticus on his way to Rome, from Tusculum, December
- XXVIII: To Atticus on his way to Rome, from Rome, December
- XXIX: To Quintus in Asia, from Rome, December