Overview

40 BC was a year marked by political realignment in the late Roman Republic and by an uncertain place in the early Julian calendar. Ancient and modern sources record it as the Year of the Consulship of Calvinus and Pollio, while chronological reconstructions differ about whether it was a common or leap year and which weekday it began on. Contemporary calendar errors left historians unsure whether the year began on a Thursday, Friday or Saturday, or whether it should be treated as a leap year starting on Thursday or Friday in the Julian calendar.

Political events and realignments

The dominant story of 40 BC is the rearrangement of power among the Second Triumvirate. After civil conflict and the brief Perusine War, leaders moved to negotiate rather than continue widespread fighting. A settlement commonly called the Treaty of Brundisium roughly partitioned spheres of influence between Octavian (the future Augustus) and Mark Antony and sought to stabilize Rome through dynastic marriage: Octavia, Octavian's sister, was given in marriage to Antony to seal the agreement. Meanwhile Sextus Pompey maintained control of Sicily and its navy, posing a continuing strategic challenge to Rome's grain supply.

Judaea and the East

In the eastern Mediterranean the Parthian intervention and local rivalries reshaped client kingships. Parthian forces and their allies captured parts of Judaea and installed Antigonus as a claimant to the throne; in response, the Roman Senate declared Herod king of Judaea, a title he would secure militarily in the following years. These shifts reflected Rome's growing influence in client states and the instability that accompanied the Republic's transformation into imperial rule.

Notable persons and consequences

  • Fulvia, the influential wife of Mark Antony whose activities helped spark the Perusine conflict, died in 40 BC while accompanying Antony's allies in the east.
  • Gaius Asinius Pollio and Gaius Calvisius Sabinus held the consulship, the year’s official magistracies.
  • The ongoing rivalry among the triumvirs and the naval dominance of Sextus Pompey set the stage for later agreements and wars that would complete Rome's shift to a single ruler.

Though not a year famed for sweeping cultural milestones, 40 BC is important for how it recorded the end of one phase of Roman civil war and the beginning of diplomatic and dynastic arrangements that would culminate in the imperial order. Calendar uncertainty from early Julian practice is a reminder that even basic chronological details can be ambiguous when ancient reforms were newly implemented.