[10] Decimus was of distinguished ancestry: his father, grandfather and great-grandfather had all been consuls,[11] and his mother was likely descended from Gaius Gracchus, the ill-fated popular reformer.
[21] Decimus Brutus spent his youth mainly in the company of Publius Clodius Pulcher, Gaius Scribonius Curio, and Marcus Antonius.
Using sickle-like hooks fitted on long poles, Decimus Brutus attacked the enemy's sails, leaving them immobilized and easy prey to Roman boarding parties.
[23] When the Republican Civil War broke out, Decimus Brutus sided with his commander, Caesar, and was entrusted once again with fleet operations.
[24] In 50 BC he married Paula Valeria, the sister of Gaius Valerius Triarius, a friend of Cicero who later fought alongside Pompey at Pharsalus.
[citation needed] In 44 BC, Decimus was made Praetor Peregrinus by personal appointment of Caesar and was designated to be the governor of Cisalpine Gaul in the following year.
He was persuaded to attend by Decimus Brutus, who escorted him to the senate house, and neatly evaded Mark Antony, who may have told Caesar of the assassination plot.
The assassins received an amnesty the next day, issued by the senate at the instigation of Mark Antony, Caesar's fellow consul.
Already in March 44 BC, Decimus Brutus found his (earlier) allocation of the province of Cisalpine Gaul opposed by Antony.
With the siege raised, Decimus Brutus cautiously thanked Octavian, now commander of the legions that had rescued him, from the other side of the river.
[32] He attempted to reach Macedonia, where Marcus Junius Brutus and Cassius had stationed themselves, but was executed en route in mid-September by a Gallic chief loyal to Mark Antony.
In Colleen McCullough's novels Caesar and The October Horse (of her Masters of Rome series) Decimus Brutus is an important character.
[38] In S.J.A Turney's series of novels titled Marius Mules, Decimus Brutus is heavily featured as a brilliant naval commander and one of Caesar's most loyal officers.