Marcus Aemilius Lepidus (Latin: M·AEMILIVS·M·F·Q·N·LEPIDVS),born ca 90 BC died 13 BC, was a patrician Roman politician of the 1st century BC who rose to become a member of the Second Triumvirate and Pontifex Maximus. His father, Marcus Aemilius Lepidus, had been involved in a rebellion against the Roman Republic which led to his death.
Lepidus was among Julius Caesar's greatest supporters. He started his cursus honorum as a praetor in 49 BC, was placed in charge of Rome while Caesar defeated Pompey in Spain, and was rewarded with the consulship in 46 BC after the defeat of the Pompeians in the East. When in February 44 BC Caesar was elected dictator for life by the senate, he made Lepidus "Master of the Horse", effectively deputy in the dictatorship. Their brief alliance in power came to a sudden end, however, when Caesar was assassinated on March 15 44 BC (the Ides of March). One of the ringleaders of the conspiracy, Cassius Longinus, had argued for the killing of Lepidus and Mark Antony as well, but Marcus Junius Brutus had overruled him, saying the action was an execution not a political coup.
After Caesar's murder, Lepidus, despite reassuring the senate of his loyalty, allied himself with Mark Antony in a joint bid for power. But Caesar had left an heir: Gaius Julius Caesar Octavian, his great nephew and adopted son. The three men met on an island in a river near Mutina (modern Modena), their armies lined along opposite banks, and formed the Second Triumvirate, legalized with the name of Triumvirs for the Organization of the People by the Lex Titia of 43 BC. Unlike the First Triumvirate of Caesar, Pompey, and Crassus, this one was formally constituted. In effect, it sidelined the consuls and the senate and signalled the death of the republic. The triumvirate's legal life span of five years was renewed in 38 BC by the treaty of Tarentum for an equal period of time.
After the pacification of the east and the defeat of the assassins' faction in the Battle of Philippi, during which he remained in Rome, Lepidus assumed rule of the western provinces of Hispania and Africa. For a while he managed to distance himself from the frequent quarrels between his colleagues Antony and Octavian; however, in 36 BC an ill-judged political move gave Octavian the excuse he needed: Lepidus was accused of usurping power in Sicily and of attempted rebellion and was forced into exile in Circeii. He was stripped of all his offices except that of Pontifex Maximus. He died peacefully in 13 BC.
Lepidus was the son of Marcus Aemilius Lepidus and Appuleia, daughter of Lucius Appuleius Saturninus. He was the brother of Lucius Aemilius Lepidus Paullus and father to Marcus Aemilius Lepidus the Younger. His wife was Junia, sister of Marcus Junius Brutus and Junia Tertia, Cassius Longinus's wife. After the Battle of Philippi, Lepidus managed to protect Junia Tertia and her mother Servilia from being executed.