Gnaeus Julius Agricola, Roman general (died 93)

AD 40 (XL) was a leap year starting on Friday of the Julian calendar. At the time, it was known as the Year of the Consulship of Augustus without colleague. The denomination AD 40 for this year has been used since the Early Middle Ages, when the Anno Domini calendar era became the prevalent method in Europe for naming years.

Gnaeus Julius Agricola was a Roman general and politician responsible for much of the Roman conquest of Britain. Born to a political family of senatorial rank, Agricola began his military career as a military tribune under governor Gaius Suetonius Paulinus. In his subsequent career, he served in a variety of political positions in Rome. In 64, he was appointed quaestor in Asia province. Two years later, he was appointed Plebeian Tribune, and in 68, he was made praetor. During the Year of the Four Emperors in 69, he supported Vespasian, general of the Syrian army, in his bid for the throne.