Olympius orchestrated the fall and execution of the capable general Stilicho, who had effectively been ruling the Western Roman Empire as regent of Honorius for over twelve years.
The weak-willed Honorius listened to the insinuations of the chancellor Olympius and proceeded to have Stilicho and his family put to immediate execution.
[1] After Stilicho's execution, Olympius prompted Honorius to take a more hostile stance toward the Goths, mostly notably Alaric I, who had previously been cooperating with the Romans.
Olympius, through Honorius, orchestrated the massacre of tens of thousands of wives and children of Goths serving in the Roman military.
Subsequently, around 30,000 Gothic soldiers defected to Alaric and took part in the first sack of Rome in 800 years, a key event in the fall of the Western Roman Empire.