For events after 404, Zosimus is the main source; he derived his information on Stilicho from two prior historians, whose texts he copies faithfully, although in summary.

In 383, Theodosius sent him as a tribunus praetorianus, an office in the branch of military administrators known as the notarii, on an embassy mission to the court of the Persian King Shapur III in Ctesiphon to negotiate a peace settlement relating to the partition of Armenia.

[11] Historians have a difficult time explaining exactly what led to his marriage to Serena which occurred after his return to Constantinople at the successful conclusion of peace talks.

[15] The last emperor of a united Rome appointed Stilicho guardian of his son Honorius, with the rank of comes et magister utriusque militiae praesentalis (supreme commander), shortly before his death in 395.

The army was still drawing the forbidden sword in that Alpine war, and conquerors and conquered gave alternate cause for dissension.

[20] Stilicho used his military leadership as well as Honorius' youth and inexperience to consolidate his authority over the empire, though he acquired many rivals and enemies in the process, both in the West and East.

After the Battle of Frigidus the Goths, under their new king Alaric, were returning to their allotted lands in Lower Moesia when they decided to raid the countryside.

Stilicho led the army, which had been victorious at the Frigidus and was still assembled in Italy, into the Balkans to confront the Goths, eventually surrounding them somewhere in Thessaly.

[21] According to Claudian, Stilicho was in a position to destroy them, but was ordered by Arcadius to return the Eastern Empire's forces and leave Illyricum.

He used the campaign to boost the morale of the western army – which had suffered three consecutive defeats in the civil wars against Theodosius – and to recruit Germanic auxiliaries to bolster its depleted ranks.

Edward Gibbon, drawing on Zosimus, criticizes Stilicho for being overconfident in victory and indulging in luxury and women, allowing Alaric to escape.

He declared his intention to place the African provinces, the critical source of Rome's grain supply, under the control of the Eastern Empire.

In 402 Stilicho returned to Italy and hastened forward with a selected vanguard in advance of his main body, breaking the siege of Mediolanum and rescuing the besieged emperor.

Stilicho, scraping together a force of c. 20,000 men (thirty numeri of Roman troops with supporting units of federates of Alans and Huns) through a variety of desperate methods, including efforts to enroll slaves in the army in exchange for their freedom, at Ticinum (Pavia) led this force at the beginning of the campaigning season in 406 against Radagaisus.

[37][38] In order to protect Italy from invasions by Alaric (401–402) and Radagaisus (405–406), Stilicho had seriously depleted the Roman forces defending the Rhine frontier.

[41] The destruction that occurred in Gaul and the lack of an effective response from the court in Ravenna lent support to the rebellion of Constantine III in Britain, which Stilicho proved unable to quash.

Sarus had some initial success, winning a major victory and killing both of Constantine's magistri militum, but a relief force drove him back and saved the rebellion.

They were angry at Stilicho for this, and one of the most outspoken of them, Lampadius, said "Non est ista pax, sed pactio servitutis (This is not peace, but a pact of servitude).

The natural consequence was that these men (estimates describe their numbers as perhaps 30,000 strong) flocked to the protection of Alaric, clamoring to be led against their enemies.

Without a strong general like Stilicho, Honorius could do little to break the siege, and adopted a passive strategy trying to wait out Alaric, hoping to regather his forces to defeat the Visigoths in the meantime.

What followed was two years of political and military manoeuvering, Alaric, king of the Goths, attempting to secure a permanent peace treaty and rights to settle within Roman territory.

He besieged Rome three times without attacking while the Roman army of Italy watched helplessly, but only after a fourth failed attempt at a deal was Alaric's siege a success.

Many historians argue that the removal of Stilicho was the main catalyst leading to this monumental event, the first barbarian capture of Rome in nearly eight centuries and a part of the fall of the Western Roman Empire.