The Gildonic War was a rebellion in the year 398 led by Comes Gildo against Roman Emperor Honorius. The revolt was subdued by Flavius Stilicho, the magister militum of the Western Roman empire.
Gildo was a Berber by birth, received in 386 as reward for his military merits from general Theodosius the Elder, father to Emperor Theodosius I, an appointment as Comes Africæ and Magister utriusque militiæ per Africam. He ruled the province as a bloodthirsty, cruel tyrant from 386 until his death in 398. This province was, after the loss of Ancient Egypt to the Eastern Roman empire, designated as the granary of Rome. Incited by the political machinations of the eunuch Eutropius, Gildo seriously entertained the notion of joining the Eastern Roman empire, which led to civil turmoil in Rome for fear of possible food shortages. Stilicho used complaints made by inhabitants of the province regarding Gildo's crimes to persuade the Senate to declare him "enemy of the State" and start a war against him.
Stilicho sent the brother of Gildo, Mascezel, together with some 5,000 Gallic veterans, to North Africa. Gibbon reports the units that formed the expeditionary force consisted of men from units whose names carried long histories of service to Rome:
These troops, who were exhorted to convince the world that they could subvert, as well as defend, the throne of an usurper, consisted of the Jovian, the Herculian, and the Augustan legions; of the Nervian auxiliaries; of the soldiers who displayed in their banners the symbol of a lion; and of the troops which were distinguished by the auspicious names of Fortunate and Invincible.
The loyalist army was countered by a force of some 70,000, consisting of the Roman legions already present in Africa, complemented with a huge cavalry of mercenaries from Gaetulia and Ethiopia.
As Mascezel approached with offers of peace, he first encountered the standard bearer of one of the African legions. When he refused to yield, Mascezel struck him on the arm with his sword. As a result, the standard-bearer lowered the standard, which was incorrectly perceived by the troops as a sign of submission. All other standard-bearers of the frontline followed the example, and the disaffected cohorts turned against Gildo and began shouting the name of their new commander. The berbers mercenaries were amazed at the disloyalty of their Roman allies and took to a tumultuous flight.
The honour of an easy and almost bloodless victory fell to Mascezel, while Gildo tried to flee in a small boat, hoping to reach the friendly shores of the Eastern Roman empire. However, unfavourable winds drove the vessel back to the harbour of Tabraca, where the inhabitants were eager to display their new loyalty by throwing Gildo in the dungeons. To avoid the revenge of his brother (Gildo had the two sons of Mascezel murdered), Gildo committed suicide by hanging.
Mascezel died shortly after his brother. On his triumphant return to the Roman court in Milan, Stilicho received him with much ceremony and jealousy. He drowned when he, in the company of Stilicho, crossed a bridge and fell in the water, either by accident, or pushed on orders of Stilicho.