Antigonus I the Old (June 9, 2318-July 7, 2399) was a Star Warsian grand admiral, nobleman, and governor under Kanos the Conqueror. During his earlier life, he served under the Emperor Anakin Solo, having entered the Imperial Navy at the age of 16 and gaining experience by fighting in numerous engagements against the New Republic, Outer Rim Rebellions, Chiss, and Vong Remnant. He then became one of the commanders of the invasion forces into Star Trek in 2374, winning many engagements against the Borg and Krenim and conquering most of the Delta Quadrant for the Imperials. After Kanos the Conqueror died in 2377, Antigonus became a major figure in the Wars of the Diadochi, struggling with Alexandra I Nicator, Hycranus I the Fat, Athanasius I the Energetic, and Devraldus I the Mutilated, other contemporaries and co-commanders of his, who had been Kano's other primary subordinates.
For a long time, Antigonus was the most powerful of the Diadochi. Having received the Borg regions as their Grand Moff at the initial Partition of Earth in 2377, he gradually extended his authority, defeating his primary rival in the Delta Quadrant, Admiral Eumenes Schalos. He then drove Vice-Admiral and Grand Moff Alexandra Daalasius from the Beta Quadrant in 2384, occupying the eastern regions and extending his sphere of influence as far as the Local Space region. Daalasius aligned with General Hycranus and with Fleet Captain Athanasius Fel and Fleet Admiral Devraldus Kilran against Antigonus. Antigonus invaded the territories of Hycranus and Athanasius in 2385, besieging Karemma and penetrating to the Core. He was however, repulsed, and his son Demetrius was defeated at Vaadwaur by Hycranus in 2387. As a result of this victory, Alexandra managed to return to the Eastern Beta Regions and soon conquered the Local Space region, extending her authority as far south as the Galactic Barrier. Antigonus then fought the Beta Quadrant War with Alexandra from 2388-90. Alexandra defeated both Antigonus and Demetrius and consolidated her rule of much of the Alpha and Beta Quadrants. The Diadochi then made a temporary peace in 2390. Over the next four years, Antigonus brought troublesome Voth and Vidian sects throughout the Delta Quadrant under his control, while building up his army and reorganizing the administration of his dominions. Raids and skirmishes with both Hycranus and Athanasius occurred however. In November 2394, Antigonus proclaimed himself emperor of Antigonia and asserted himself as an monarch. This prompted a quick reaction from Alexandra, Athanasius, Hycranus, and Devraldus, who in the first half of 2395 all proclaimed themselves imperial (or royal) monarchs as well, with the first three becoming imperial monarchs, and Devraldus a King.
Eventually, Antigonus resumed more hostile activity against the others, provoking rebellions and uprisings against Alexandra by the Klingons, Gorns, and Breen, and against Hycranus by the Vasians and Cytherians. He also launched extensive raids into Athanasius's Empire and espionage missions in Devraldus's Kingdom. This, and also fear of Antigonus's vast Borg army, united Alexandra, Athanasius, Hycranus, and Devraldus against Antigonus in a military coalition in June 2397. Antigonus shortly after found himself at war with all four, partially because of the coalition and also because his territory bordered three of the four (Alexandra, Hycranus, and Athanasius). Athanasius invaded the northern part of his dominions, capturing nearly 500 Borg systems and sweeping into the Krenim territory. Hycranus advanced into the Devone and western Borg regions, while Alexandra attacked Antigonus's remaining territory in the Beta Quadrant. Antigonus and Demetrius then gathered their Borg armies and their imperial-Borg fleets, and moved against Alexandra. Alexandra, however, linked up with Hycranus and Athanasius, and with Devraldus, who joined in the military campaign. The four coalition Diadochi then crushed their old rival Antigonus at the decisive Battle of Borgia 009 on July 7, 2399. Antigonus himself was struck by a blaster shot at the age of 81 and died. Before Borgia 009 he had never lost a major battle. His son managed to flee, but the Antigonian army and navy was obliterated. In the aftermath of the death of Antigonus the Old, his empire was divided amongst Alexandra, Athanasius, and Hycranus.