Aulus Caecina Alienus, Roman general, was quaestor of Hispania Baetica (southern Iberia) in AD 68.
On the death of Nero, he attached himself to Galba, who appointed him to the command of a legion in upper Germany. Having been prosecuted for embezzling public money, Caecina went over to Vitellius, who sent him with a large army into Italy.
Caecina crossed the Alps, but was defeated near Cremona by Suetonius Paulinus, the chief general of Otho. Subsequently, in conjunction with Fabius Valens, Caecina defeated Otho at the decisive battle of Bedriacum (Betriacum).
The incapacity of Vitellius tempted Vespasian to take up arms against him. Caecina, who had been entrusted with the repression of the revolt, turned traitor, and tried to persuade his army to go over to Vespasian, but was thrown into chains by the soldiers.
After the overthrow of Vitellius, he was released, and taken into favor by the new emperor. But he could not remain loyal to any one. In 79 he was implicated in a conspiracy against Vespasian, and was put to death by order of Titus.
Caecina is described by Tacitus as a man of handsome presence and boundless ambition, a gifted orator and a great favourite with the soldiers.