Calgacus was the first Caledonian (inhabitant of present-day Scotland) mentioned in Roman sources. Tacitus describes him as the leader of the Caledons, a man of self-respect and an excellent orator. He had red hair and a powerful build. His name in the Celtic language meant “having a sword”.
According to Tacitus, in 84 CE Calgacus, in response to the intensifying offensive of Julius Agricola (governor of Britain from 77 CE) was to give a fiery speech (which was probably made up) and stimulate the crowd to fight against the Romans. He gathered an army of over 30,000 and in the Grampians (the so-called Battle of Mons Graupius) he faced the Roman army led by Agricola. Despite the defeat, Calgacus managed to make peace, which shows the great respect Romans had for the Caledonians.