Basiliscus, likely of Balkan origin, is the brother of Aelia Verina, wife of Leo I.

It has been argued that Basiliscus was uncle to the chieftain of the Heruli, Odoacer.

This link is based on the interpretation of a fragment by John of Antioch (209.1), which states that Odoacer and Armatus, Basiliscus' nephew, were brothers.

However, not all scholars accept this interpretation, since sources do not say anything about the foreign origin of Basiliscus.

It is known that Basiliscus had a wife, Zenonis, and at least one son, Marcus.

Basiliscus' military career had started under Leo I, when the Emperor conferred upon his brother-in-law the dignities of dux, or commander-in-chief, in Thrace.

In this country, Basiliscus had led a successful military campaign against the Bulgars in 463.

Succeeding Rusticius as magister militum per Thracias in 464, he had had several successes against the Goths and Huns (466 or 467).

Basiliscus's value had risen in Leo's consideration.

Verina's intercession in favor of her brother has helped Basiliscus' military and political career, with the conferral of the consulship in 465 and possibly of the rank of patricius.

However, his rise is soon to meet a serious reversal.

In 468, Leo chooses Basiliscus as leader of the later famous military expedition against Carthage.

The invasion of the kingdom of the Vandals is one of the greatest military undertakings recorded in the annals of history, a combined amphibious operation with over ten thousand ships and one hundred thousand soldiers.

The purpose of the operation is to punish the Vandal king Genseric for the sacking of Rome in 455, in which the former capital of the Western Roman Empire had been overwhelmed, and the Empress Licinia Eudoxia (widow of Emperor Valentinian III) and her daughters had been taken as hostages.

Ancient and modern historians provide different estimations for the number of ships and troops under the command of Basiliscus, as well as for the expenses of the expedition.

Both are enormous; Nicephorus Gregoras speaks of one hundred thousand ships, the more reliable Cedrenus says that the fleet that attacked Carthage consisted of eleven hundred and thirteen ships, having each one hundred men on board.

The most conservative estimation for expedition expenses is of sixty-four thousand pounds of gold, a sum that exceeds a whole year's revenue.

It is the greatest fleet ever sent against the Vandals; the expense brings Leo near to bankruptcy.

Marcellinus was supposed to have a command of some ten thousand to twenty thousand troops.

Marcellinus had never sailed for Africa, perhaps due to Ricimer's veto; either he would not spare so many troops to become bogged in a campaign in Africa, hoping the East would do the job for him, or he resented the military capabilities of Marcellinus who was obviously the favorite of Anthemius.

Regardless of the reason, Marcellinus’s inabiity to participate in the campaign, coupled with Basiliscus’s blundering in the Battle of Cape Bon, assured that the operation would result in failure.

The West has lost its only chance to regain Africa from the Vandals and possibly stave off its demise.

Marcellinus is reached in Sicily by Basiliscus; the general is, however, assassinated, perhaps at the instigation of Ricimer, by one of his own captains; and the king of the Vandals expresses his surprise and satisfaction that the Romans themselves would remove from the world his most formidable antagonists.

The Vandals reconquer Sicily, administering a decisive defeat to the Western forces.

Pope Leo’s twenty-one-year reign is followed by that of Hilarius, who reigns for seven years, followed in 468 by the election of Simplicius.

The Roman plan of attack is concerted between Eastern Emperor Leo, Western Emperor Anthemius, and General Marcellinus, who enjoys independence in Illyricum.

Basiliscus is ordered to sail directly to Carthage, while Marcellinus attacks and takes Sardinia, and a third army, commanded by Heraclius of Edessa, lands on the Libyan coast east of Carthage, making rapid progress.

It appears that the combined forces met in Sicily, whence the three fleets moved at different periods.

Sardinia and Libya have already been conquered by Marcellinus and Heraclius, when Basiliscus casts anchor off the Promontorium Mercurii, now Cap Bon, opposite Sicily, about forty miles from Carthage.

Genseric requests Basiliscus to allow him five days to draw up the conditions of a peace.

During the negotiations, Geiseric gathers his ships and suddenly attacks the Roman fleet.

The Vandals had filled many vessels with combustible materials.

During the night, these fire ships are propelled against the unguarded and unsuspecting Roman fleet.

The Eastern Roman commanders try to rescue some ships from destruction, but these maneuvers are blocked by the attack of other Vandal vessels.

Basiliscus flees in the heat of the battle.

One half of the Roman fleet is burned, sunk, or captured, and the other half follow the fugitive Basiliscus.

The entire expedition has failed.

Heraclius effects his retreat through the desert into Tripolitania, where he will hold the position for two years until recalled.

Suebi Raids and the Sack of Conimbriga (465–468 CE)

Under the leadership of Remismund, the Suebi resume their raids, plundering Lusitania and the Conventus Asturicense, while also continuing their struggles against unsubdued Galician tribes, such as the Aunonenses, who inhabit an island in the Atlantic Ocean, identified as modern Ons.

In 465 CE, the Suebi breach part of the walls of Conimbriga in Lusitania, looting the wealth of the noble Cantabri family. Three years later, in 468 CE, the Suebi sack Conimbriga, forcing most of its inhabitants to flee to Aeminium (modern Coimbra), while others are captured and taken north as slaves. After this devastation, Conimbriga is largely abandoned, marking a significant shift in the region’s urban landscape.

The Roman Emperor Leo I supports an anti-Goth coalition of German tribes, despite the advice of his General Aspar.

The two sides meet in 469 near the river Ipeľ in present day Slovakia and Hungary in an engagement called in the Battle of Bolia.

Theodomir leads his Goths in a decisive victory over the combined forces of Heruli, Rugii, Scirii, and Suebi.

A group of Suebi had settled in parts of Pannonia after the Huns were defeated in 454 in the Battle of Nedao.

The Suebian king Hunimund fights against the Ostrogoths at Bolia.

After the Suebian coalition loses the battle, parts of the Suebi therefore migrate to southern Germany.

Basiliscus, who had returned to Constantinople after the disastrous expedition against the Vandals, had been forced to seek sanctuary in the church of Hagia Sophia to escape the wrath of the people.

Leo I had given him imperial pardon, but had banished him for three years to Heraclea Sintica (Thrace).

Zeno, as member of the protectores domestici, had not taken part in the expedition.

In 469, during which he holds the honor of the consulate, he is appointed magister militum per Thracias and leads an expedition in Thrace.

The sources do not clearly state what enemy he fought there, and historians had proposed either Goths or Huns, or the rebels of Anagastes.

Either way, before leaving, Leo and Zeno had asked for Daniel the Stylite's opinion about the campaign, and Daniel had answered that Zeno would have been the target of a conspiracy but would have escaped unharmed.

What happened was that Leo had sent some of his personal soldiers with Zeno to protect him, but they had been bribed by Aspar to actually capture him.

Zeno had been informed of their intention and fled to Serdica, and because of this episode, Leo grows even more suspicious of Aspar.

After the attack, Zeno had not returned to Constantinople, where Aspar and Ardabur are and have still considerable power.

Instead, he moves to the "Long Wall" (the Chersonese Long Wall or, less probably, the Anastasian Wall), then to Pylai and from there to Chalcedon.

While waiting here for an opportunity to return in the capital, he is appointed magister militum per Orientem.

He takes the monk Peter the Fuller with him and leaves for Antioch, his office's see, passing through Isauria, where he puts down the rebellion of Indacus.

The Vandals invade Epirus (modern Albania).

Expelled from the Peloponnese (Greece), the Vandals, in retaliation, take five hundred hostages at Zakynthos: they are slaughtered on the way back to Carthage.

King Euric declares his kingdom independent from the Western Roman Empire in 469.